Mafia
Mafia is a forum game, based on those goddamn murder mystery parties, only, it's actually good.
It requires a certain extent of Namefaggotry to play, attempts to run mafia on a chan have all failed.
The people who this wikifag plays it with(Penny Arcade forumers) call it Phalla, because
1.FUCKING PUBBIES
2.They luurve teh kawkz.
3.There is no third one, the other ones stand on their own.
4.Actually, there is, they are much more ballsy when it comes to rules, and themes, and do not worship the first game as a sacred cow.
Many PA games have had surprise shit going on in the background, see this 1984/Vendetta game http://forums.penny-arcade.com/showthread.php?t=71082 where the majority of the population secretly believed in democracy, and, thanks to yours truly day one bandwagoning a man because he signed up in Cyan the entire fucking population was bent around Big Brother's finger and goddamnit, it fits the fucking book so perfectly.
If you have not yet read the book or seen the BLACK AND WHITE movie, go read/watch it.
Fucking irony, why do you have to destroy civilization?