Eraser is from Downward Spiral, many versions out there on youtube, here's one. My favorite NIN for sex.Malice said:Eraser? You mean Erasure?
http://www.youtube.com/watch?v=cF2vFzracxc
For Lords of Acid, crab louse, taste my honey, machoman. Curve is also good, lunatic calm mix of chinese burn if you have a gym rat used to aerobics music.
Of course the best music strategy is whatever they like that makes them want to do a strip tease before f-ck. Then wait til round 2 or so to put in your music and get things lively again.