Obviously, Caligula has brief gay sex in straight scenes, if you can FF past the gross stuff. (To this day I firmly believe that's why Caligula is still a popular movie: open gay sex in a crowd of straight fucking.) Shortbus is the only move I've ever seen that made gay sex look boring, straight sex look disturbed, and the most inane dialog of any porno. Ever. Don't bother renting it, it's not worth the buck. What's the diff between porn and art? If a guy cums on his own face and then cries, it's art.
While most bi movies leave be cold, "Mass Appeal" was completely hot and steamy, still one of my favorites.
IMHO, the three things "mainline" porn completely misses are:
1- Guys who like their butt played with during oral,
2- Women who actually get wet during foreplay (Talking to you, Vivid!)
3- Guy on guy contact during MMF or orgies. It's a major mood breaker when the male performers react like they all have cooties or something. Hey director! I'm pretty sure the two cocks you have pumping in and out of the biker chick on screen, did not get there by themselves! Stop cutting that "grope and poke" footage out of the movie!
There used to be a website called "Watch us fuck", one of the clips there was so hot: this guy is laying down on his back, his GF is riding his cock in her ass, facing his feet.
She leans back and pumps a vibrator into her wet pussy while cumming over and over. THEN she takes the vibrator and rims the guys butt with it, slowly teasing his ass until she finally drives it deep in him. He comes hard, his cock popping out of her ass and splashing DNA all over both of them.
Scuze me, I'll be right back