I don't think anyone mentioned Maurice - excellent movie and book(
http://www.imdb.com/title/tt0093512/)
I agree with some other posts - to me some of the best gay movies aren't the gay tragedies, coming-out sagas or love stories, but:
Bring It On
Moulin Rouge
Clueless
Mean Girls
and how can a good gay pass up "Troop Beverly Hills"?
http://www.imdb.com/title/tt0098519/