I used to just click the knuckles on my hands. Now I click my knuckles, jaw, shoulders, hips, knees, ankles, feet and toes. Generally I keep the full thing to myself though... it freaks people out if they walk in and I'm leaning to the side to click my inner hip.
I also chew my finger nails and toe nails, pull out my hair one individual follicle at a time.
I have this hand shake thing which is probably my favourite stim. At work if I'm stressed I'll sometimes nip to the bathroom just to get it out of my system. When I'm home, and listening to music, I'll start off just shaking my hands till the fingers blur, but I'll keep it up till my whole arms and shoulders are joining in with it. It's like my arms want to start dancing, but it goes from my fingers up to my shoulder blades. I've seen pictures of myself as a kid, and there's not one picture where my hands are in focus before the age of about five. I'm pretty sure I'm doing my handy dance.
The worst one I ever did though was get into lotus position at school, stick my head between my legs, and scuttle across the floor in the middle of assembly. I was seven, and I always remember one girl crying because she thought I looked like a spider. When I heard her say that I freaked out, and couldn't unlock myself... so I was screaming and scuttling round the room with a whole gaggle of nuns chasing me.
I can't remember how I got out of that one.
Anyway... clicking and hand dancing, probably my weirdest.