If you like playing gambling games and you're cheap like me, then you might like this deal. Most of those online gambling sites allow you to play the games without using real money, and the games are quite well done. It appears that many of the casinos license the same software and just stamp their casino's name on it. The games are quite well done, though. For a while I played some of that Sierra Casino stuff, but I've found that for stuff like blackjack and roulette that this is just as good.
One that I've been playing is Powerbet
. They've got a deal right now where you get $20 free for signing up (no cc required), but you can only withdraw the money if you can grow it to $100. Lucky me, I was able to get up to $112 in Three Card Poker, and I'm in the process of getting my cash (they use a paypal clone for money transfer).