A Bronx Tale is also a very good one, how could I forget. And I thought about Casino, but while it gives an pretty accurate presentation of the mob in Vegas, it doesn't really show the usual daily activities of mobsters like you see in Goodfellas. And Mean Streets isn't a real "mobster" film, but it does show the mob's environment extremely realistic.
"It was between the brothers Kay -- I had nothing to do with it."
