westfw:
Slag from the homemade fireworks, dripping down my wrist after I picked up the burning device to run to hide from my parents...
Interesting (and faint, by now) scar. Probably part chemical burn, but quite shallow...
I burned a couple fingers with canon fuse once. Probably was more painful than I appreciated ... uh, beer was a factor. 
The MAPP gas torch does a nice burn too. ]