I worked on one soft porn movie. No penetration, late night Cinemax stuff. It was pretty funny shooting the sex scenes. We had wireless receivers so we could hear the action and peek around the corner while they were doing the scenes.
The director was this fat goofy guy and he would be saying "More breathing, more tounge, pull her hair", so the guy pulls her hair and she gets all pissed off, "Don't pull it that hard!"
We did this one lesbo scene and both the chicks were named Jennifer. "Okay, now Jennifer you get on top." They would both move for a sec and then get confused. The starlett got to be called by her real name and the B girl was called by her character name.
That movie was called "Mischevious" (sp?) and you can find it at some video stores. I actually have a couple cameos as "Dude in Prison Cell" and "Dude on the corner with the whores". Those are my usual hangouts so it was no big stretch.
I worked on one that was a titty music video stripper montage kinda thing. It was pretty tame but this one chick was getting pretty nasty on the pool table. I remember the camera man looking up and asking "Can we even use that?".