BitLotto
A lottery style gambling site with 99% payout.
The winning selection of lottery numbers for determining the winner or winners are the results of the Western Canada Lottery Corporation draw.
The Bitcoin address used to purchase the lottery entry contains the "pick". The algoritm for converting the winning lotto numbers to the characters from the entrant's Bitcoin address is documented on the site.
The service was launched on April 6th, 2011[1].
Criticism
When a winner is paid out the bitcoin amount is sent to the Bitcoin address used to buy the lottery entry. This method is not compatible with EWallet services and and payouts iwll not go to the intended recipient. The site does warn about this but some users who use an eWallet might not realize the issue.