So if you wanted to see sex in 3-D, a good place to start is Hard Candy. I caught that at the Music Box a bunch of years back with Kate and was quite entertained. It isn't a one trick pony either; it's also a period piece.
As there's porn on the mind, apparently, some readers among you may wish to check out a new book called Robot Porn. Tiffany managed to snag an advance copy through Bishop's University and it is definitely worth a read… if you like angsty rambling and inventive expletives.
If you don't want to see sex in 3-D, and instead want to watch a bad 80's horror movie's gimmicky third installment, you've got at least three choices: Amityville 3-D, Jaws 3-D, and Friday the 13th Part 3-D. I honestly don't remember anything about Amityville, but of the others, they're both sufficiently painful.