Have your man sit on top of the washing machine while you have sex (you on top, with your legs wrapped around him). Can also work with a woman with a dildo and her partner wrapping around her.
The vibrations carry through his penis, turning him into a wonderful vibrator. For the best results, select the cotton cycle. It's a warm wash so his butt won't get cold, plus it has the longest, fastest spin. Good clean fun.
