My friends are promoting their fantasy sports site, based on bitcoin, called CoinRoster.
The bitcoins can be used to play on CoinRoster, but they can’t be withdrawn until they have been played 20 times, which in this case is 0.40 bitcoins worth of play.
For those of you who are unfamiliar with bitcoins, at the time of writing these 0.02 bitcoins are worth about $40 Canadian dollars or $25 US dollars.
I’d say the best games they currently offer are about Golf. They have a weekly golf fantasy game and also have a daily hockey game. In the summer they tell me they’ll have a baseball game going and in the fall they will do NFL.