Matrix trilogy - specially one and three. One for its ingenuity and new-ness, and three for its epic battle scene in the dock.
Chasing Amy - the superior Kevin Smith film, but Clerks and Jay and Silent Bob Strike Back are cool too
Hitchcock. Anything, and I mean anything. Particularly Psycho and the Birds.
The Third Man - Orson Welles cheeky grin.
Kill Bill vol.1 and 2 probably.
Reservoir Dogs... "Are you gonna bark all day, little Doggie, or are you gonna bite?"
Pulp Fiction of course.
From Dusk Til Dawn for the incredible screenplay twist
oh, and the original Airplane! but Airplane! 2: the sequel is equally as hilarious.
Theres my twopenny
You can kiss my flat-ass