For free casino games, facebook’s sloto mania is one of the best I have found to play. The owners of sloto mania have been adding new slots quite often bringing the total slots games to 21 right now, with the latest game added on Nov 11, 2011.
They have a decent variety of slot machines all with bonus rounds and free spins. One of the best features is that every 4 hours the player is credited with a bonus so they can continue playing the slots, the higher the level you obtain the larger the bonus is.
Then after you have collected the bonuses 4 times, you will get a big special bonus where you spin the wheel to see what you will be rewarded. This comes with 3 bonuses, one the amount on the wheel, then a % based on how many facebook friends you have playing with you and how many you have referred to the sloto mania game. If you enjoy just playing slots for fun, this is a highly addictive free casino game.