Bitcoin Wiki - User contributions [en]

Altcoin

2020-06-15T15:42:51Z

Bitcoinmuc: fix typo/grammar

{{seealso|List of alternative cryptocurrencies}}
Altcoins are cryptocurrencies other than Bitcoin.

The majority of altcoins are forks of Bitcoin with small uninteresting changes. This page categorises different ways altcoins have modified Bitcoin.

Many people prefer the term "shitcoin" to clearly distinguish all these altcoins from Bitcoin. This term has even been used in US Congress.

==Different proof-of-work algorithm==

The PoW algorithm used for mining Bitcoin is SHA2.
It was chosen because it is fast to verify and has been critically analyzed.
SHA2 has had ASICs developed for it meaning there is a much smaller risk of centralization.
The following mining algorithms are being used in different altcoins:

*[[Scrypt proof of work]]
*Combination of hashing algorithms in series (e.g. X11)
*Combination of hashing algorithms in parallel (e.g. Myriad algorithm)

The problem with having an algorithm that is "easy to mine with" (referring to the ability to CPU or GPU mine profitably) is that mining should be hard in order to secure the network. When a mining algorithm is difficult to make ASICs for, there is a higher barrier to entry. A high barrier to entry increases the time that the first group to create ASICs will monopolize the market (and the time the network is vulnerable to a 51% attack from a single source). Many argue that the creators or the developers could simply change the mining algorithm when an ASIC is developed, but this defeats the purpose of decentralized consensus by causing centralization.<ref>[https://download.wpsoftware.net/bitcoin/asic-faq.pdf ASIC FAQ]</ref>

If these cryptocurrencies do have a healthy number of companies producing ASICs and have avoided centralization, they still are using algorithms that take longer to verify than SHA2. Therefore, at best a cryptocurrencies with merely a hashing algorithm change are as good as an exact clone of Bitcoin and not better (however since Bitcoin already exists, an exact clone of Bitcoin has no innovation or value). If the hashing algorithm is slower, as most altcoin algorithms are, it is a disadvantage because it takes more processing time to validate a block and increases the number of organic re-orgs (makes it easier to double spend).

==Proof Of Stake==

In [[Proof of Stake]], instead of sacrificing energy to mine a block, a user must prove they own a certain amount of the cryptocurrency to generate a block. The more stake you own, the more likely you are to generate a block. In theory, this should prevent users from creating forks because it will devalue their stake and it should save a lot of energy.

Proof of Stake sounds like a good idea, but ironically, there is the "Nothing at Stake" problem. Because mining Bitcoin is costly, it is not smart to waste your energy on a fork that won't earn you any money, however with Proof of Stake, it is free to mine a fork.

An example of a nothing at stake attack is an attacker buying lots of "old stake" from users inexpensively (inexpensive to users who no longer have stake in the currency). This can be made convenient by offering small payments to users for uploading their wallet.dat. Eventually after accumulating enough "old stake", the user can begin creating blocks and destroying as many or more coin days than the network was at that time. This block generation can be repeated until it catches up to and beats the current main-chain very cheaply.

There are also "stake grinding" attacks which require a trivial amount of currency. In a stake<ref>[https://bitcointalk.org/index.php?topic=131901.0 Peercoin Security Analysis]</ref> grinding attack, the attacker has a small amount of stake and goes through the history of the blockchain and finds places where their stake wins a block. In order to consecutively win, they modify the next block header until some stake they own wins once again. This attack requires a bit of computation, but definitely isn't impractical.

Because these attacks exists, including Peercoin<ref>[https://github.com/ppcoin/ppcoin/blob/master/src/checkpoints.cpp#L370 Peercoin Source | Centralized Checkpointing Public Key]</ref> and Blackcoin<ref>[https://github.com/rat4/blackcoin/blob/master/src/checkpoints.cpp#L361 Blackcoin Source | Centralized Checkpointing Public Key]</ref> proof of stake cryptocurrencies have "master" public keys that control the blockchain.

This class of cryptocurrency is either insecure or centralized, however proof of stake (based on a PoW currency) is useful in some systems because gaining stake is costly, but it isn't workable for bootstrapping distributed consensus.

==Application Built on Top of a Cryptocurrency==

Bitcoin is a lot like HTTP. It is an application layer protocol and tools can be built on it (like websites can be built on HTTP). There is a class of cryptocurrencies that promise features like casino websites and exchanges and anonymity protocols to be built on top of them.

When creating a new website, one doesn't make a new protocol unless it is necessary. For example, HTTPS is an encrypted version of HTTP, therefore it is useful and necessary. When creating an app such as "[https://bitcointalk.org/index.php?topic=467857.0 DarkSend]", one doesn't need to make a new protocol such as "Darkcoin". This is synonymous to making an HTTPS alternative (eg. HTTPSX) for your new encrypted chat website and not adding any new security or functionality to HTTPSX.

Because Darkcoin is by far the most popular cryptocurrency of this class, the Darkcoin example will be covered in this section.

The Darkcoin devs created a tool called DarkSend. DarkSend is an implementation of coinjoin (an anonymity feature originally implemented in Bitcoin<ref>[https://bitcointalk.org/index.php?topic=279249.0 Coinjoin Outline | BitcoinTalk]</ref>) which utilizes the Darkcoin network to organize the coinjoins. If DarkSend becomes open source and is useful, it will be ported to Bitcoin with a few small modifications. These changes won't be a hardfork, they will likely involve the masternodes being paid by those they are coinjoining for rather than the block reward, which is already possible and implemented for Bitcoin. <ref>[https://www.wpsoftware.net/coinjoin/ Rotating Coinjoiner]</ref>Currently one must hold 1000DRK to become a DarkSend masternodes. Masternodes are paid 10% of the block reward.<ref>[https://darkcointalk.org/threads/darkcoin-update-masternode-requirements-masternode-payments.225/ DarkSend Payment Scheme]</ref> This is a flawed reward scheme because while purchasing 1000DRK is trustlessly verifiable, a user running a DarkSend masternode isn't trustlessly verifiable. It is also costs bandwidth to run a masternode, therefore there is an incentive to buy 1000DRK and get a chance at the 10% block reward masternodes are being paid, but not actually act as a masternode. For this reason, DarkSend would work better if the masternodes were paid by those they were helping coinjoin, or if there wasn't a masternode at all and everyone collaborated in a decentralized fashion. The better implementation not vulnerable to tragedy of the commons is compatible with Bitcoin, therefore, the Darksend protocol serves no purpose.

==Demographic Based Premined Cryptocurrencies==

This is a new class of altcoin that is targeted at a certain demographic.

All of these cryptocurrencies have a large premine intended to be paid to members of that demographic. Ultimately, all of these coins have suffered (or are suffering) their fate of an immediate sell off after the "[[airdrop]]" (term for distribution of coins to the target demographic) begins.

Note: These cryptocurrencies aren't government initiatives, but are independently created for that demographic.

==Useful Cryptocurrencies==

A cryptocurrency is useful if it accomplishes a task that Bitcoin cannot.

*Acting as a keystore for things like decentralized domain registration.
*Having demmurage or some other economic system that is one of the [[prohibited changes]].
*Allowing creation of and transmission of digital assets.

==References==
<references/>

Meetups

2017-08-01T13:14:12Z

Bitcoinmuc:

Don't add everyone who's going in the "Who?" column, just prominent Bitcoin members and organizers. Also see [http://bitcoin.meetup.com bitcoin.meetup.com]. Also see [[Conferences]].

Keep an eye on the [http://bitcointalk.org/index.php?board=86.0 Meetups] forum board on BitcoinTalk for announcements.

{| class="wikitable"
|-
! Group
! When?
! Where?
! Who?
! Other Notes
|-
| [http://www.meetup.com/Bitcoin-in-San-Diego/ Bitcoin in San Diego]
| Bi-Monthly meetups, weekly workshops
| San Diego, CA, United States
| Local and international participants - guest speakers welcome.
| Presentations and workshops, discussion & trade.
|-
| [http://www.meetup.com/Tucson-Bitcoin-Marketplace/ Bitcoin in Tucson]
| short-notice meetups
| Tucson, AZ, United States
| everyone welcome
| breakfast, Bitcoin basics, presentations, cryptocurrencies, blockchains, and economics
|-
| [http://www.meetup.com/blockchaintech/ Blockchain Tech in Phoenix]
| regular and short-notice meetups
| Phoenix, AZ, United States
| everyone welcome
| hack-a-thons and anything directly or indirectly related to blockchain technology!
|-
| [http://bitcoinembassy.ca Bitcoin Embassy]
| Monthly meetups, weekly workshops
| Montreal, QC, Canada
| Local and international participants - guest speakers welcome. Come and visit our hackerspace, startup incubator and soon, Bitcoin store.
| Presentations and workshops, discussion & trade. [http://eepurl.com/GRzAf Register to our mailing list] to receive event invitations. We also post on [https://bitcointalk.org/index.php?board=86.0 BitcoinTalk Meetups], [http://bitcoinembassy.eventbrite.ca/ EventBrite], [https://www.facebook.com/bitcoinembassy Facebook Bitcoin Embassy page], [https://plus.google.com/u/0/100266464273886488866 Google +], etc.
|-
|-
| [http://www.meetup.com/San-Antonio-Bitcoin/ San Antonio Meetup]
| Every Thursday at 7:00 PM
| San Antonio, Texas
Currently at [https://www.google.com/maps/place/17711+Interstate+10+Frontage+Rd,+The+Rim,+San+Antonio,+TX+78257/@29.609714,-98.59871,17z/data=!3m1!4b1!4m2!3m1!1s0x865c6423ecd5d047:0xaa94c89b14a98fc0 Tiago's]
| Miners, entrepreneurs, traders and anyone looking to learn more about Bitcoin and other Cryptocurrencies are welcome.
| [https://bitcointalk.org/index.php?topic=727155.0 Bitcointalk thread]
|-
|-
| [http://www.meetup.com/BitcoinCT/ BitcoinCT Meetup]
| Monthly Meetups
| Stamford, CT
| The Connecticut Bitcoin Meetup brings together Bitcoin users in Connecticut. This meetup is suitable for everyone from Bitcoin newbies to experienced Bitcoiners. You can attend meetups simply to learn more about Bitcoin or to make business connections for entrepreneurs, miners and developers. | We welcome everyone to our meetups even if you're not currently a Bitcoin user, but simply want to find out more about this amazing e-currency.
|-
|-
| [https://bitcash.cz/forum/ Bitcash.cz]
| Ocasionally
| Prague, Brno, Ostrava
| Meetup for Czech and Slovak bitcoin pioneers.
| Discuss and trade with Bitcoin. Events posted also on our [https://www.facebook.com/Bitcash.cz Facebook] profile.
|-
|-
| [http://www.meetup.com/Sydney-Bitcoin-Users-Group/ BitcoinSYD]
| Every Wednesday @ 1800
| [https://goo.gl/maps/okdSm The SG], Downstairs, 32 York St. Look for the guy in the Red Cap.
| Local, National and International peeps looking to Talk and Trade Bitcoin
| We also post our meetups on Reddit and [https://www.facebook.com/pages/Bitcoin-Sydney-Australia/457681220943285 Facebook]
|-
|-
| [https://bitcointalk.org/index.php?topic=27191.0;all Bitcoin Stammtisch]
| each first Thursday of the month
| [http://www.room77.de/ Room 77], Gräfestr. 77, Berlin-Kreuzberg
| Anyone interested in Bitcoin: technically, economically, socially or philosophically.
| If questions contact andreas(at)schildbach.de (founder).
|-
|-
| [http://www.meetup.com/Nashville-Bitcoin-Meetup/ Nashville Bitcoin Meetup]
| weekly and quarterly
| Nashville, TN
| Plenty of room for all!
|
|-
| [http://www.meetup.com/bitcoins/ Bitcoin NYC]
| monthly
| [http://www.xcubicle.com/ xCubicle Hackerspace - New York, NY]
| Any and all Bitcoin aficionados.
|
|-
|-
| [https://en.bitcoin.it/wiki/Bitcoin_Wednesday Bitcoin Wednesday Amsterdam]
| First Wednesday of the Month
| Dutch Bitcoin Users Group of the Netherlands - The country's longest continuously running Bitcoin event.
| [http://www.meetup.com/BitcoinWednesday/ Sign Up - Amsterdam, The Netherlands]
| Open to anyone interested in Bitcoin. Organized by [https://www.PikaPay.com PikaPay.com] @PikaPay or hello-AT-PikaPay.com
|-
|-
| [http://hitspace.org/ HIT Space - Hack it Together]
| monthly
| [http://hitspace.org/where-we-are/ HIT Space - Porto, Portugal]
| Hackerspace members and anyone who want to join us
| send us an email geral[at]hitspace.org
|-
|-
| [http://bitcoin-austria.at Bitcoin Austria]
| monthly - check the [http://bitcoin-austria.at wiki] or subscribe to the [http://lists.bitcoin-austria.at/listinfo/bitcoin mailinglist]
| [https://metalab.at/wiki/Lage Metalab], Vienna hacker space, Rathausstraße 6, 1010 Wien
| Everybody interested in Bitcoin
|
|-
| [http://brmlab.cz brmlab, prague hackerspace]
| 14th Nov 2011
28th Nov 2011
([http://brmlab.cz/event/bitcoin_seminar])
| [http://brmlab.cz/place Brmlab, Bubenska 1]
| brmlab crew, slush, genjix
|
|-
| [http://www.facebook.com/groups/175596065827848/ Bitcoin Boston]
| Every Friday at 4:30 and bi-weekly on Saturday or Sunday ([http://www.facebook.com/groups/175596065827848/ See Facebook page])
| Starbucks in Kendall Square (Ames St & Broadway) and bi-weekly at Starbucks in Harvard Square
| Anyone is welcome!
| Our bi-weekly meetings have been somewhat sporadic but we aim to gain some regularity.
|-
| [http://www.meetup.com/Milwaukee-Area-Bitcoin-Meetup/ Milwaukee Area Bitcoin Meetup]
| Every other Thursday at 6:00pm
| 17025 West Rogers Drive, New Berlin WI
| Open to anyone interested in Bitcoin
| [https://www.facebook.com/groups/BTCMKE Milwaukee Area Bitcoin Meetup Facebook]
|-
| [http://www.meetup.com/bitcoin New York Bitcoin Users]
| 6:00 PM, 3rd Sunday of every month ([http://www.meetup.com/bitcoin/events/past past meetings])
| OnlyOneTV Studios - 290 Fifth Ave New York, NY
| Bruce Wagner (Organizer) and others
|
|-
|-
| [http://www.meetup.com/bitcoin New York Bitcoin Users]
| 6:00 PM, every Wednesday of every month ([http://www.meetup.com/bitcoin/events/past past meetings])
| Just Sweet Dessert House - 83 Third Ave New York, NY
| Yifu Guo (Organizer) and crew
| hosted by Bitsyncom, the people behind [[Bitnavigator]], walk-ins welcome;
|-
|[http://www.meetup.com/MichiganBitcoinMeetup Michigan Bitcoin Meetup]
|
|
|Kinnard Hockenhull (Organizer)
|Sponsored by [[BitBox]]
|-
| [http://www.meetup.com/PhillyBitcoin Philadelphia Bitcoin User Group]
| TBD
| TBD
| Brian Cohen (Organizer) and others
|
|-
| [http://www.meetup.com/BitcoinDC Washington, DC Bitcoin Users]
| 7:00 PM, 1st Monday of every month ([http://www.meetup.com/BitcoinDC/#past past meetings])
| Northside Social, 3211 Wilson Blvd Arlington, VA
| [[User:Dduane|Darrell Duane]] (Organizer) and others
|
|-
| [http://www.meetup.com/Silicon-Valley-Bitcoin-Users Silicon Valley Bitcoin Users]
| 7:00 PM, Tuesday, June 14, 2011 ([http://www.meetup.com/Silicon-Valley-Bitcoin-Users/events/past past meetings])
| 140B S Whisman Road Mountain View, CA
| Brian Mcqueen and others
|
|-
| [http://www.meetup.com/BitcoinChicago Chicago]
| No regular schedule yet ([http://www.meetup.com/BitcoinChicago/events/past past meetings])
| Sunnyvale Art Gallery Cafe, 251 W El Camino Real Sunnyvale, CA
| Igor
|
|-
| [http://www.meetup.com/denver-bitcoin Denver]
| First meeting June 4th, 2011 ([http://www.meetup.com/denver-bitcoin/events/past past meetings])
| Gypsy House Cafe - 1279 Marion St Denver, CO
| bearbones
|
|-
| [http://www.meetup.com/SF-Bitcoin-Devs/ SF Bitcoin Devs]
| About twice a month ([http://www.meetup.com/SF-Bitcoin-Devs/#past past meetings])
| San Francisco, CA
|
| This meetup has a strong technical/engineering focus ([https://www.youtube.com/channel/UCREs0ConyCR2sEFf-DrLRMw see videos of past presentations])
|-
| [http://www.meetup.com/San-Francisco-Bitcoin-Social/ San Francisco Bitcoin Social]
| Every second Thursday and last Tuesday of the month ([http://www.meetup.com/San-Francisco-Bitcoin-Social/#past past meetings])
| San Francisco, CA
|
| More general (less technical) meetup for cryptocurrency aficionados
|-
| [http://www.meetup.com/Los-Angeles-Digital-Currency-Innovators-Group Los Angeles Digital Currency Innovators]
| Thursday July 7th, 2011, 7 PM
| (mt)/Media Temple, Culver City, CA
| [[User:sgornick|Stephen Gornick]] (Interim organizer) and others
| Seeking meetup coordinator
|-
| [http://CryptoParty.vegas/ Las Vegas Crypto Party]
| 1st Thursday 7pm. [http://BitcoinsInVegas.com Weekly Wednesday lunch mobs]
| CoinBus.com, 64 N Pecos, Henderson, NV 89052
| Julian Tosh / Tuxavant
|
|-
| [https://www.facebook.com/groups/195492163844669/ Free State Bitcoin Consortium]
| Every Saturday, at 6:30 PM
| Strange Brew Tavern, Manchester, NH
| ben-abuya (organizer)
| Weekly
|-
| [https://www.facebook.com/groups/195492163844669/ Twin Cities Users]
| Friday, June 10, 2011, 6:30 PM
| Joule - 1200 Washington Ave S Minneapolis, MN
| Mac Manson
|
|-
| [http://www.meetup.com/Bitcoin-of-South-Florida/ Bitcoin of South Florida] and [http://www.meetup.com/Miami-International-Bitcoin-Group/ Miami International Bitcoin]
| Rotated weekly
| Miami, Ft. Lauderdale, and Boca Raton, FL
| All party people are welcome
|-
| [http://www.meetup.com/Bitcoin-Orlando Bitcoin Orlando]
| ([http://www.meetup.com/Bitcoin-Orlando#past past meetings])
| Frank & Steins 150 S. Magnolia Ave, Orlando, FL
| Antonio Gallippi
|
|-
| [http://www.meetup.com/Bitcoin-Enthusiasts/ Bitcoin Tampa]
| Monthly meetings
| Matt Branton -- [https://www.coinlock.com/ Coinlock.com] founder
|
|-
| [http://www.hive13.org/?p=310 Hive13 Hackerspace]
| Bitcoin Exchange, Every Tuesday, 7:30 PM
| Hive13 - 2929 Spring Grove Avenue, Cincinnati, OH
|
|
|-
| [https://www.facebook.com/bitcoinaus Bitcoin Australia]: Melbourne
| [https://www.facebook.com/events/345430765511234/ Wednesday, 23 May 2012, 18:45]
| Melbourne CBD(TBA)
| Facebook, IRC, Bitcointalk Forum...
|
|-
| [[Bitcoin Wiki:Tokyo meetup|Tokyo]]
| Every Thursday
| Shibuya, Roppongi
| Roger Ver (Organizer) and others
| Locations change, check the meetup page
|-
| [http://meetup.com/Bitcoin-Canada Vancouver Canada]
| ([http://www.meetup.com/Bitcoin-Canada/#past past meetings])
| The Brickhouse - 730 Main St.
| humble (and others)
|
|-
| [https://plus.google.com/u/0/communities/113055238568417913658 Zurich / Geneva Switzerland]
| Twice a month
| Kennedy's Irish Pub, Zurich; Lord Nelson Pub, Geneva
| Stefan Thomas (WeUseCoins), Mike Hearn (BitcoinJ), bitdragon, Luzius (Wuala), more ...
|
|-
| Seattle Bitcoin Meetup
| [http://www.meetup.com/SeattleBitCoin/ Semi-regularly].
| [http://maps.google.com/maps?q=cafe+solstice&daddr=4116+University+Way,+Seattle,+WA+98105-6214&hl=en&ll=47.657424,-122.31313&spn=0.007328,0.01929&gl=us&view=map&geocode=CRT9Bdg7zX3vFdcx1wIdWqa1-CFcJ9qrr9CcEQ&t=h&z=16 Solstice Cafe, 2pm]
| [https://bitcointalk.org/index.php?action=profile;u=36217 indolering]
|
|-
| [https://bitcointalk.org/index.php?topic=135723.0 Bitcoin Munich]
| Stammtisch (regular get-together) every first Wednesday of a month, 6pm, plus at least one additional event (talks or workshop) each month in various locations.
| [https://www.openstreetmap.org/node/1969699757 Wirtshaus am Bavariapark], Theresienhöhe 15, 80339 München
| Long-time Bitcoin users from Munich; mostly low profile but we've been around. ;) Plus international visitors.
| [http://www.meetup.com/Bitcoin-Munich/ meetup.com/Bitcoin-Munich/]
|-
| [http://www.meetup.com/bitcoin-il/ Israel Bitcoin Meetup Group]
| Occasional
| TBD
| Meni Rosenfeld
|
|-
| [http://www.meetup.com/Dallas-Bitcoin-User-Meetup/ Dallas Bitcoin Meetup Group]
| Biweekly on Saturdays, 6:00PM
| [http://freemandallas.com/ The Free Man Cajun Cafe]
| Justus Ranvier (organizer)
|
|-
| [https://en.bitcoin.it/wiki/Cafe Café Bitcoin Sevilla]
|
| Seville, Spain
| Randy Brito (rdymac / btcven), Eduardo (bitcoin.com.es), Jorge and Alfredo
| http://cafebitcoin.com
|-
| [http://www.meetup.com/BitcoinSingapore/ Bitcoin Singapore Meetup]
|
| Singapore
| Monthly
| [https://www.facebook.com/pages/Bitcoin-Singapore/431452580303555 Bitcoin Singapore Facebook Page]
|-
| [http://www.meetup.com/Lehigh-Valley-Bitcoin-Meetup/ Lehigh Valley (Allentown/Bethlehem PA) Bitcoin]
|
| Westgate Subway; Schoenersville Rd; Bethlehem
| Jim Hoff (organizer)
| http://www.meetup.com/Lehigh-Valley-Bitcoin-Meetup/
|-
| [http://www.meetup.com/LetsUseBitcoin/ Lets Use Bitcoin]
| Monthly
| {{flag|nl}}
| Local and international participants
| Using Bitcoin, discussion of bitcoin and having fun! Sponsored by [[BTC.com]]
|-
| [http://www.meetup.com/Arnhem-Bitcoin-Users Arnhem Bitcoin Users]
| Monthly
| Arnhem Bitcoincity (the Netherlands)
| Beginners and experts
| Spend some time (and bitcoins) in the most Bitcoin-friendly city!
|-
|}

==See Also==

* [http://hackerspaces.org/wiki/List_of_Hacker_Spaces List of Hacker Spaces]
* [http://bitimap.net Bitimap.net - Find local meetups (up-to-date)]

[[Category:Local]]
[[Category:Meetups]]

[[de:Treffen]]

Meetups

2017-08-01T13:11:27Z

Bitcoinmuc:

Don't add everyone who's going in the "Who?" column, just prominent Bitcoin members and organizers. Also see [http://bitcoin.meetup.com bitcoin.meetup.com]. Also see [[Conferences]].

Keep an eye on the [http://bitcointalk.org/index.php?board=86.0 Meetups] forum board on BitcoinTalk for announcements.

{| class="wikitable"
|-
! Group
! When?
! Where?
! Who?
! Other Notes
|-
| [http://www.meetup.com/Bitcoin-in-San-Diego/ Bitcoin in San Diego]
| Bi-Monthly meetups, weekly workshops
| San Diego, CA, United States
| Local and international participants - guest speakers welcome.
| Presentations and workshops, discussion & trade.
|-
| [http://www.meetup.com/Tucson-Bitcoin-Marketplace/ Bitcoin in Tucson]
| short-notice meetups
| Tucson, AZ, United States
| everyone welcome
| breakfast, Bitcoin basics, presentations, cryptocurrencies, blockchains, and economics
|-
| [http://www.meetup.com/blockchaintech/ Blockchain Tech in Phoenix]
| regular and short-notice meetups
| Phoenix, AZ, United States
| everyone welcome
| hack-a-thons and anything directly or indirectly related to blockchain technology!
|-
| [http://bitcoinembassy.ca Bitcoin Embassy]
| Monthly meetups, weekly workshops
| Montreal, QC, Canada
| Local and international participants - guest speakers welcome. Come and visit our hackerspace, startup incubator and soon, Bitcoin store.
| Presentations and workshops, discussion & trade. [http://eepurl.com/GRzAf Register to our mailing list] to receive event invitations. We also post on [https://bitcointalk.org/index.php?board=86.0 BitcoinTalk Meetups], [http://bitcoinembassy.eventbrite.ca/ EventBrite], [https://www.facebook.com/bitcoinembassy Facebook Bitcoin Embassy page], [https://plus.google.com/u/0/100266464273886488866 Google +], etc.
|-
|-
| [http://www.meetup.com/San-Antonio-Bitcoin/ San Antonio Meetup]
| Every Thursday at 7:00 PM
| San Antonio, Texas
Currently at [https://www.google.com/maps/place/17711+Interstate+10+Frontage+Rd,+The+Rim,+San+Antonio,+TX+78257/@29.609714,-98.59871,17z/data=!3m1!4b1!4m2!3m1!1s0x865c6423ecd5d047:0xaa94c89b14a98fc0 Tiago's]
| Miners, entrepreneurs, traders and anyone looking to learn more about Bitcoin and other Cryptocurrencies are welcome.
| [https://bitcointalk.org/index.php?topic=727155.0 Bitcointalk thread]
|-
|-
| [http://www.meetup.com/BitcoinCT/ BitcoinCT Meetup]
| Monthly Meetups
| Stamford, CT
| The Connecticut Bitcoin Meetup brings together Bitcoin users in Connecticut. This meetup is suitable for everyone from Bitcoin newbies to experienced Bitcoiners. You can attend meetups simply to learn more about Bitcoin or to make business connections for entrepreneurs, miners and developers. | We welcome everyone to our meetups even if you're not currently a Bitcoin user, but simply want to find out more about this amazing e-currency.
|-
|-
| [https://bitcash.cz/forum/ Bitcash.cz]
| Ocasionally
| Prague, Brno, Ostrava
| Meetup for Czech and Slovak bitcoin pioneers.
| Discuss and trade with Bitcoin. Events posted also on our [https://www.facebook.com/Bitcash.cz Facebook] profile.
|-
|-
| [http://www.meetup.com/Sydney-Bitcoin-Users-Group/ BitcoinSYD]
| Every Wednesday @ 1800
| [https://goo.gl/maps/okdSm The SG], Downstairs, 32 York St. Look for the guy in the Red Cap.
| Local, National and International peeps looking to Talk and Trade Bitcoin
| We also post our meetups on Reddit and [https://www.facebook.com/pages/Bitcoin-Sydney-Australia/457681220943285 Facebook]
|-
|-
| [https://bitcointalk.org/index.php?topic=27191.0;all Bitcoin Stammtisch]
| each first Thursday of the month
| [http://www.room77.de/ Room 77], Gräfestr. 77, Berlin-Kreuzberg
| Anyone interested in Bitcoin: technically, economically, socially or philosophically.
| If questions contact andreas(at)schildbach.de (founder).
|-
|-
| [http://www.meetup.com/Nashville-Bitcoin-Meetup/ Nashville Bitcoin Meetup]
| weekly and quarterly
| Nashville, TN
| Plenty of room for all!
|
|-
| [http://www.meetup.com/bitcoins/ Bitcoin NYC]
| monthly
| [http://www.xcubicle.com/ xCubicle Hackerspace - New York, NY]
| Any and all Bitcoin aficionados.
|
|-
|-
| [https://en.bitcoin.it/wiki/Bitcoin_Wednesday Bitcoin Wednesday Amsterdam]
| First Wednesday of the Month
| Dutch Bitcoin Users Group of the Netherlands - The country's longest continuously running Bitcoin event.
| [http://www.meetup.com/BitcoinWednesday/ Sign Up - Amsterdam, The Netherlands]
| Open to anyone interested in Bitcoin. Organized by [https://www.PikaPay.com PikaPay.com] @PikaPay or hello-AT-PikaPay.com
|-
|-
| [http://hitspace.org/ HIT Space - Hack it Together]
| monthly
| [http://hitspace.org/where-we-are/ HIT Space - Porto, Portugal]
| Hackerspace members and anyone who want to join us
| send us an email geral[at]hitspace.org
|-
|-
| [http://bitcoin-austria.at Bitcoin Austria]
| monthly - check the [http://bitcoin-austria.at wiki] or subscribe to the [http://lists.bitcoin-austria.at/listinfo/bitcoin mailinglist]
| [https://metalab.at/wiki/Lage Metalab], Vienna hacker space, Rathausstraße 6, 1010 Wien
| Everybody interested in Bitcoin
|
|-
| [http://brmlab.cz brmlab, prague hackerspace]
| 14th Nov 2011
28th Nov 2011
([http://brmlab.cz/event/bitcoin_seminar])
| [http://brmlab.cz/place Brmlab, Bubenska 1]
| brmlab crew, slush, genjix
|
|-
| [http://www.facebook.com/groups/175596065827848/ Bitcoin Boston]
| Every Friday at 4:30 and bi-weekly on Saturday or Sunday ([http://www.facebook.com/groups/175596065827848/ See Facebook page])
| Starbucks in Kendall Square (Ames St & Broadway) and bi-weekly at Starbucks in Harvard Square
| Anyone is welcome!
| Our bi-weekly meetings have been somewhat sporadic but we aim to gain some regularity.
|-
| [http://www.meetup.com/Milwaukee-Area-Bitcoin-Meetup/ Milwaukee Area Bitcoin Meetup]
| Every other Thursday at 6:00pm
| 17025 West Rogers Drive, New Berlin WI
| Open to anyone interested in Bitcoin
| [https://www.facebook.com/groups/BTCMKE Milwaukee Area Bitcoin Meetup Facebook]
|-
| [http://www.meetup.com/bitcoin New York Bitcoin Users]
| 6:00 PM, 3rd Sunday of every month ([http://www.meetup.com/bitcoin/events/past past meetings])
| OnlyOneTV Studios - 290 Fifth Ave New York, NY
| Bruce Wagner (Organizer) and others
|
|-
|-
| [http://www.meetup.com/bitcoin New York Bitcoin Users]
| 6:00 PM, every Wednesday of every month ([http://www.meetup.com/bitcoin/events/past past meetings])
| Just Sweet Dessert House - 83 Third Ave New York, NY
| Yifu Guo (Organizer) and crew
| hosted by Bitsyncom, the people behind [[Bitnavigator]], walk-ins welcome;
|-
|[http://www.meetup.com/MichiganBitcoinMeetup Michigan Bitcoin Meetup]
|
|
|Kinnard Hockenhull (Organizer)
|Sponsored by [[BitBox]]
|-
| [http://www.meetup.com/PhillyBitcoin Philadelphia Bitcoin User Group]
| TBD
| TBD
| Brian Cohen (Organizer) and others
|
|-
| [http://www.meetup.com/BitcoinDC Washington, DC Bitcoin Users]
| 7:00 PM, 1st Monday of every month ([http://www.meetup.com/BitcoinDC/#past past meetings])
| Northside Social, 3211 Wilson Blvd Arlington, VA
| [[User:Dduane|Darrell Duane]] (Organizer) and others
|
|-
| [http://www.meetup.com/Silicon-Valley-Bitcoin-Users Silicon Valley Bitcoin Users]
| 7:00 PM, Tuesday, June 14, 2011 ([http://www.meetup.com/Silicon-Valley-Bitcoin-Users/events/past past meetings])
| 140B S Whisman Road Mountain View, CA
| Brian Mcqueen and others
|
|-
| [http://www.meetup.com/BitcoinChicago Chicago]
| No regular schedule yet ([http://www.meetup.com/BitcoinChicago/events/past past meetings])
| Sunnyvale Art Gallery Cafe, 251 W El Camino Real Sunnyvale, CA
| Igor
|
|-
| [http://www.meetup.com/denver-bitcoin Denver]
| First meeting June 4th, 2011 ([http://www.meetup.com/denver-bitcoin/events/past past meetings])
| Gypsy House Cafe - 1279 Marion St Denver, CO
| bearbones
|
|-
| [http://www.meetup.com/SF-Bitcoin-Devs/ SF Bitcoin Devs]
| About twice a month ([http://www.meetup.com/SF-Bitcoin-Devs/#past past meetings])
| San Francisco, CA
|
| This meetup has a strong technical/engineering focus ([https://www.youtube.com/channel/UCREs0ConyCR2sEFf-DrLRMw see videos of past presentations])
|-
| [http://www.meetup.com/San-Francisco-Bitcoin-Social/ San Francisco Bitcoin Social]
| Every second Thursday and last Tuesday of the month ([http://www.meetup.com/San-Francisco-Bitcoin-Social/#past past meetings])
| San Francisco, CA
|
| More general (less technical) meetup for cryptocurrency aficionados
|-
| [http://www.meetup.com/Los-Angeles-Digital-Currency-Innovators-Group Los Angeles Digital Currency Innovators]
| Thursday July 7th, 2011, 7 PM
| (mt)/Media Temple, Culver City, CA
| [[User:sgornick|Stephen Gornick]] (Interim organizer) and others
| Seeking meetup coordinator
|-
| [http://CryptoParty.vegas/ Las Vegas Crypto Party]
| 1st Thursday 7pm. [http://BitcoinsInVegas.com Weekly Wednesday lunch mobs]
| CoinBus.com, 64 N Pecos, Henderson, NV 89052
| Julian Tosh / Tuxavant
|
|-
| [https://www.facebook.com/groups/195492163844669/ Free State Bitcoin Consortium]
| Every Saturday, at 6:30 PM
| Strange Brew Tavern, Manchester, NH
| ben-abuya (organizer)
| Weekly
|-
| [https://www.facebook.com/groups/195492163844669/ Twin Cities Users]
| Friday, June 10, 2011, 6:30 PM
| Joule - 1200 Washington Ave S Minneapolis, MN
| Mac Manson
|
|-
| [http://www.meetup.com/Bitcoin-of-South-Florida/ Bitcoin of South Florida] and [http://www.meetup.com/Miami-International-Bitcoin-Group/ Miami International Bitcoin]
| Rotated weekly
| Miami, Ft. Lauderdale, and Boca Raton, FL
| All party people are welcome
|-
| [http://www.meetup.com/Bitcoin-Orlando Bitcoin Orlando]
| ([http://www.meetup.com/Bitcoin-Orlando#past past meetings])
| Frank & Steins 150 S. Magnolia Ave, Orlando, FL
| Antonio Gallippi
|
|-
| [http://www.meetup.com/Bitcoin-Enthusiasts/ Bitcoin Tampa]
| Monthly meetings
| Matt Branton -- [https://www.coinlock.com/ Coinlock.com] founder
|
|-
| [http://www.hive13.org/?p=310 Hive13 Hackerspace]
| Bitcoin Exchange, Every Tuesday, 7:30 PM
| Hive13 - 2929 Spring Grove Avenue, Cincinnati, OH
|
|
|-
| [https://www.facebook.com/bitcoinaus Bitcoin Australia]: Melbourne
| [https://www.facebook.com/events/345430765511234/ Wednesday, 23 May 2012, 18:45]
| Melbourne CBD(TBA)
| Facebook, IRC, Bitcointalk Forum...
|
|-
| [[Bitcoin Wiki:Tokyo meetup|Tokyo]]
| Every Thursday
| Shibuya, Roppongi
| Roger Ver (Organizer) and others
| Locations change, check the meetup page
|-
| [http://meetup.com/Bitcoin-Canada Vancouver Canada]
| ([http://www.meetup.com/Bitcoin-Canada/#past past meetings])
| The Brickhouse - 730 Main St.
| humble (and others)
|
|-
| [https://plus.google.com/u/0/communities/113055238568417913658 Zurich / Geneva Switzerland]
| Twice a month
| Kennedy's Irish Pub, Zurich; Lord Nelson Pub, Geneva
| Stefan Thomas (WeUseCoins), Mike Hearn (BitcoinJ), bitdragon, Luzius (Wuala), more ...
|
|-
| Seattle Bitcoin Meetup
| [http://www.meetup.com/SeattleBitCoin/ Semi-regularly].
| [http://maps.google.com/maps?q=cafe+solstice&daddr=4116+University+Way,+Seattle,+WA+98105-6214&hl=en&ll=47.657424,-122.31313&spn=0.007328,0.01929&gl=us&view=map&geocode=CRT9Bdg7zX3vFdcx1wIdWqa1-CFcJ9qrr9CcEQ&t=h&z=16 Solstice Cafe, 2pm]
| [https://bitcointalk.org/index.php?action=profile;u=36217 indolering]
|
|-
| [https://bitcointalk.org/index.php?topic=135723.0 Munich Germany]
| Stammtisch (regular get-together) every first Wednesday of a month, 6pm, plus at least one additional event (talks or workshop) each month in various locations.
| [https://www.openstreetmap.org/node/1969699757 Wirtshaus am Bavariapark], Theresienhöhe 15, 80339 München
| Bitcoin users from Munich; mostly low profile but we've been around. ;) Plus international visitors.
| [http://www.meetup.com/Bitcoin-Munchen/ @meetup.com]
|-
| [http://www.meetup.com/bitcoin-il/ Israel Bitcoin Meetup Group]
| Occasional
| TBD
| Meni Rosenfeld
|
|-
| [http://www.meetup.com/Dallas-Bitcoin-User-Meetup/ Dallas Bitcoin Meetup Group]
| Biweekly on Saturdays, 6:00PM
| [http://freemandallas.com/ The Free Man Cajun Cafe]
| Justus Ranvier (organizer)
|
|-
| [https://en.bitcoin.it/wiki/Cafe Café Bitcoin Sevilla]
|
| Seville, Spain
| Randy Brito (rdymac / btcven), Eduardo (bitcoin.com.es), Jorge and Alfredo
| http://cafebitcoin.com
|-
| [http://www.meetup.com/BitcoinSingapore/ Bitcoin Singapore Meetup]
|
| Singapore
| Monthly
| [https://www.facebook.com/pages/Bitcoin-Singapore/431452580303555 Bitcoin Singapore Facebook Page]
|-
| [http://www.meetup.com/Lehigh-Valley-Bitcoin-Meetup/ Lehigh Valley (Allentown/Bethlehem PA) Bitcoin]
|
| Westgate Subway; Schoenersville Rd; Bethlehem
| Jim Hoff (organizer)
| http://www.meetup.com/Lehigh-Valley-Bitcoin-Meetup/
|-
| [http://www.meetup.com/LetsUseBitcoin/ Lets Use Bitcoin]
| Monthly
| {{flag|nl}}
| Local and international participants
| Using Bitcoin, discussion of bitcoin and having fun! Sponsored by [[BTC.com]]
|-
| [http://www.meetup.com/Arnhem-Bitcoin-Users Arnhem Bitcoin Users]
| Monthly
| Arnhem Bitcoincity (the Netherlands)
| Beginners and experts
| Spend some time (and bitcoins) in the most Bitcoin-friendly city!
|-
|}

==See Also==

* [http://hackerspaces.org/wiki/List_of_Hacker_Spaces List of Hacker Spaces]
* [http://bitimap.net Bitimap.net - Find local meetups (up-to-date)]

[[Category:Local]]
[[Category:Meetups]]

[[de:Treffen]]