10: Subject transcripts. Not entirely serious, but I was thinking of the transcripts being typed up in the film "Brazil", which were all "AHHH, OH GOD, NO, DON'T, WHAT IS THAT YOU'RE PUTTING ON MY HEAD".

How about a temporal displacement device that lets you fuck yourself from five minutes into the future? If you don't finish before then, you get caught in a kind of temporal loop where you're doing it with yourself in five minutes' time, who is doing it with yourself from ten minute's time. That could get really messy.

It could also be used on females and Cboys to sufflate the labia and clitoris, which increases sensitivity, although that might end up being a separate thing.