Ever heard of Mafia? It's a popular parlor game where there's two sides, Mafia and Civilian, and they try to find out who the "mafia" is and lynch them without lynching too many of their own kind. It's based on tricky psychological work and Machiavellian scheming.
Werewolf is Mafia, but on steroids. A full game is 32 players, with 8 "wolves" (mafia) and 24 "villagers" (civilians). Plus, it's on a forum, and lasts several weeks. So there's the added element of communications, networking, and very complicated social logic.
We're trying to start a round on Friday, March 9th with as many people as we can get. Everyone and anyone is welcome.
If you're confused about the rules, here's an excellent read about it.