I'm afraid of people touching the backs of my knees/insides of my elbows. Brrrr. A friend of mine once scratched (lightly!) the back of my knee while I was asleep on a couch and I kicked him in the head before I'd fully woken up.

Also slightly afraid of getting in/getting out of elevators. It's that little transition period between solid floor and floor that could move without warning. Eeek.