What are the best lesser known mafia movies?

I've just been playing the Mafia games and have been getting all caught up in it and have a hankering to watch a good mafia movie.

The problem is I've seen most of the popular ones, (marooooone!!!) like Godfather, Scarface, Bronx Tale, Goodfellas, Snatch, Eastern Promises and TV wise, of course, The Sopranos.

What are the best lesser known ones that I may not have seen yet? Nothing overtly comical (not looking for comedy crime movies) or arthouse, please. Just a good movie.