Betting with no registration. Starcraft2 and other games
We are now ready to take new bets! Saturday, 19 May is the finals in GSL season 2.
How does it work?

Every match has two or more Bitcoin betting addresses. 
A payment of any amount to this address is considered a bet. 
After the event, all the Bitcoins from the loosing pool minus 
the fee are distributed amongst the winners according to the amount they have placed. 
In addition all winners of course get back their original bet.

http://backcoin.com/