Gangster films:
State of Grace
Miller's Crossing
King Of New York
New Jack City
The Long Good Friday

Non-gangster films
The Big Lebowski(Funniest movie ever!)
Glengarry Glen Ross(One of Pacino's best movies)
Raising Arizona
Fargo
The Third Man
Boyz N The Hood
Menace II Society
Midnight Express
The Deer Hunter
Deliverance
Full Metal Jacket