I couldn't add the following titles even though they're on IMDb: 'Nights in black Leather' (1973) is narcissist Peter Berlin's most famous blue movie and very telling as to how ancient certain fetishes are. I'm gradually including more titles so feel free to come back every once in a while.
I'm only listing films with a recognizable LGBT angle, not exploitative ones or those where it's a matter of interpretation (for instance, Hitchcock's 'Rope' can only be interpreted as gay-themed if one knows the real-life case by which it was inspired - and in 'Spartacus', you got to catch on to what oysters are supposed to mean). It's got a long way to go so bear with me. Since quite a few people seem to use this list for reference, I'm revamping and upgrading it into two halves.