The Warriors (post above) is a great film. Of course it's entirely comic strip and you can almost see the bubbles from the characters' mouths when they speak ("The chicks are packed!")
My list would include the following:
The Night of the Hunter (Robert Mitchum at the peak of his powers which went way beyond his usual type casting as tough army sergeant as the evil preacher with 'LOVE' and 'HATE' tattoo'd on his knuckles)
Bull Durham (Kevin Costner isn't a favorite of mine but he is excellent, along with Susan Sarondon, in this romantic comedy set in one of baseball's minor leagues. Said to be a favorite of Billy Wilder (who of course made Some Like It Hot).
The Big Lebowski (some great fucking dialogue and epic performances from Jeff Bridges and John Goodman, not to mention a hilarious cameo from John Turturro as 'Jesus' - "And that rug really held the room together, did it not?")
The Exiles (great footage of the now gone Bunker Hill neighbourhood in LA; the subject matter is a group of Native Americans off the Rez and their eventful lives as they socialise, drink, dance, gamble and brawl in the big city in the early 60s when it was made).
Zulu (perhaps the greatest war film ever made - I don't think it really needs any introduction from me here - saw it when it came out at the Kentish Town ABC cinema [now The Forum] when I was about 8 or 9 when screens were truly big - the next week the whole school was playing Zulu in the playground, a few playing the soldiers behind a little wall, the great majority, including me, playing the charging Zulus - scared the teachers shitless!)
Also got a soft spot for the near-epic Little Big Man.