I use(d) Full Tilt Poker, Ultimate Bet, Absolute Poker, and PokerStars. My favorite is Full Tilt Poker, and that is really the only one I use these days. With the whole collusion thing... the sites are monitered to watch for cheating, whether it be two players working together, or someone using a pokerbot, etc. Sites won't let two different accounts from the same ISP, or even the same household log in at the same time. Basically, you don't have to worry about being shafted while playing online poker