American Film Institute's Top 100 Films
I'm not quite sure if the title of this list is accurate... They're obviously favoring the classics, at the great cost of excellent films that followed on the heels of them. I was shocked at how many I've actually seen, some of which I don't think have any business as high as they are (Singin' in the Rain at 5? Godfather II on this list at all? Shane above The Wild Bunch?)
The AFI also obviously snubbed foreign films. Still, a decent list of classics.