BitLotto was an online lottery. It failed to distribute the payout from March 2013 so further wagering is not recommended.
The April 4th, 2012 lotto was the first to accommodate multi-ticket purchases (i.e., send an amount that equals the number of tickets times the per-ticket price).
On March 17th, 2012 an affiliate program was introduced which allows ticket purchases using an address assigned to the affiliate. The affiliate earns a 1% commission on all ticket purchases made towards that affiliates address.
The method for choosing a winner was revised using an improved method beginning with the April 6, 2012 and subsequent draws. BitLotto uses a public processes that selects the winner but a an independent party built an open source tool to verify the results (Java).
The March 2013 winner has not been paid out. The site's operator has not provided an explanation.
When a winner is paid, the funds are sent to the Bitcoin address that bought the winning entry. If the user buys the ticket using an eWallet service those funds are lost as any winnings will then go to someone else. The site does clearly provide a warning about this, however.
Unlike other gambling sites, BitLotto requires Bitcoin payments in this specific manner because of how tickets are tracked and winnings paid out. BitLotto has chosen to operate in this way to increase the transparency of the lottery.