So, I'm dealing with a minor tantrum spiral at the moment, doesn't seem to be threatening the long-term viability of the fortress, just some unhappy dwarves. My fortress is built into a cliff cut by a river, so I have a bridge going from the front door to the little grassy valley on the other side of the river where I keep my animals. As I was looking around, I saw an unhappy dwarf just standing on the bridge, doing nothing, and my first thought was, jokingly, "don't do it, Tobul!". I checked his status, it said attending meeting, so I figured he was trying to find the mayor, and his pathfinding got held up a little. I moved on. About thirty seconds later, I get the message "Tobul Egastrovod, Clothier, has drowned." I zoom, and there he is, dead at the bottom of the river.
I'm shocked, because I thought the dwarves had to explicitly go melancholy before they could kill themselves. As I'm pondering this question, I cruise up a few z levels, and I find the bridge is gone. He must have tantrumed, and broke the bridge while he was standing on it. This was a big, solid, obsidian bridge, mind you, so the mental image is kind of ridiculous. And awesome.
Anyway, nothing too exciting, just thought I'd share. Anybody else have tantruming dwarves accidentally off themselves in hilarious ways?