I have discovered a series of games on FaceBook that allow you to play other games and things like this:

Mafia Wars
Vampire Wars
Empire Battle
Dante's Inferno
And recently I found a Dungeon and Dragons Mod that uses 4th gen rules to roleplay in short missions and quests. I got my hands on a set of 4th ed books, and have never been able to totally throw myself into it. The rules are odd, they seem to be trying to "streamline" a lot of things that I thought were streamlined enough. Needless to say, I am -impressed- with it. You can't pick actions, you outfit your character based off of a template, and items you have. The "shop" offers you several items that you may or may not be able to use based on your character and such. You can accept the offer, leave it alone until you have the money, or reject it outright should you decide the item has no use for you whatsoever, (ie- this item can only be used by clerics and you are playing a ranger.)

Anyone else have a system or a game they might have encountered elsewhere that is awesome like this?