The Graduate Mafia Brotherhood
The Graduate Mafia Brotherhood of Princeton is a bunch of fellows who play an interesting game known as mafia. There are three mafiosi, one angel and any number of citizens. The game is divided into day and night: during the night, all players close their eyes and then the mafiosi awake and designate a citizen for assassination; then they go back to sleep and the angel wakes up; he points to one player and is informed by the moderator whether that player is mafia or citizen; in the morning the assassinated player is found dead; then the players all vote to convict and kill a single one of their number. The goal of the mafia is to kill off all citizens; the goal of the citizens is to kill off all the mafia.
The page has a number of variations. One of the more interesting is to combine mafia and werewolf (which is the same game, but with werewolves, a seer and townsfolk): the mafia and werewolves are fighting one another and killing off civilians. Best played with a large number of players, I imagine.

