O come on, you got your pick. Godfather trilogy Snatch Pulp Fiction Goodfellas Once upon a time in New York The Cotton Club Road to Perdition Casino Sexy Beast
groovy list TerminalMadness , i wouldn't have thought of mentioning 'Snatch' but that is an uberweird movie afew others i can think of: Scarface The Last Don Harlem Nights Stop! or my mom will shoot
Donnie Brasco is a great movie with Al Pacino and Johnny Depp, plus it's based on a true story. Also you can watch any Sopranos episode It's great too
If you're in the mood for a mafia comedy, try Mafia! It has Jay Mohr, LLoyd Bridges, and some other funny actors. It's basically a parody of The Godfather, but there are other parodies, as well.