coppola has some great endings:
godfather 1, 2 & 3 all have awesome different endings.
the conversation (AWESOME ENDING)
bram stoker's dracula (surprising sad ending)
Kill Bill 1 (yes)
also: Jackie Brown
PTA has the Boogie Nights and There Will be Blood endings.
2001, Shinning, Clockwork and Eyes Wide Shut.
Melancholia was incredible. Ditto Dancer in the Dark and Dogville.
Reygadas's Silent Light somehow manages to become as resonant as Ordet.
I personally love the ending for the Coen's The Man Who Wasn't There and No Country for Old Men.
The 400 Blows.
Probably my all time favorite ending for any movie is 8 1/2.
And it may not be a movie, but I think the ending for The Sopranos was a moment of true genius.