Cosa Nostra is one of those unrealistically long games which requires too many people with too much energy and imagination to play. Nevertheless I'm going to give it a go some time in August. It vaguely resembles Monopoly, Diplomacy, Go and LARP, and I think it's flexible enough to be called a roleplaying game. The rules look complicated but they're not really. Most of the rules only affect a few of the players involved, and they're quite intuitive and easy to follow. The combat system is extremely simple and (to my knowledge) original (though I'm sure we could find someone who's invented it before).
Feel free to run a game of Cosa Nostra yourself, but if you do, let me (firstname.lastname@example.org) know how it went and how I can improve the system! As it's untested I'm sure most of the numbers need fiddling and some of the rules can safely be cut.
I've nearly finished, but I'm still looking for suggestions for another 50 or so ideas for Civilian Events Cards.