I started a thread on the Dope for a game of "The Resistance", which is not mafia, but does have some similarities (an informed minority versus a uninformed majority). My thread is sinking like a stone, though. If you would like to play go over and sign up (I only need a minimum of 5 players). If people are interested but would rather play here, I can move the game. Just tell me which forum to put it in. Also, I was trying to pace the game to have it move along rather quickly, but if players would rather I gave more time to the various phases, I could do that.
I have played a live version of this game and it is really fun. I was just wanting to see how well it translates to message board play or what changes would need to be made.