Here is a nice game based on flip coin with, (apparently ?) better rate than SatoshiDice:
http://minefield.bitcoinlab.org/?r=45MJDnBFoolHpnrx
 
You can even play for free, just sparing some time.
-> You choose an amout (0 to 5 btc)
-> You choose the number of mine on the field
-> Each click on an empty mine make you increase your % of reward
-> You can stop and get your reward at anytime !
 
Have fun ~