Instrumental injuries.

So I was idly thinking last night about injuries -- or not so much injuries; physical changes in general -- associated with particular musical instruments. For instance, anyone who's played violin (or viola in my case) knows the "violinist's hickey," that red welt on your neck where the instrument presses in. And string players develop fingertip calluses.

I have distinct sore spots (sometimes blisters) on specific parts of my fingers after playing handbells, depending on exactly which bells I'm playing with which techniques. I can't think of any other way I'd end up with these particular sore spots (and eventual calluses, I suppose).

If you play an instrument, what are the distinctive physical marks it leaves on you?