So then I came home tonight, and my X server was wedged again (as it is wont to do) but this time when I killed it from another machine, my left monitor was doing this wonky thing where it looks like every column of 32 bits is transposed, and it's all seething/shimmering like bad television reception. Yay. When this has happened before, powering the machine all the way off for a while has fixed it, but not this time. Yay. So now I've got all my windows wedged into the right monitor (which can only run in 8-bit mode, for reasons best left unexplored.)
Then, failing to heed the abundantly clear warning signs that I should just go to bed, I popped off some keys to see if I could figure out what was going wrong with the keyboard. Oh look, it's not a membrane keyboard: there are springs.
Ten minutes later I found the spring.
Thirty minutes later, I had rendered the 1, 2, and 3 keys non-operational as well, and gave up and ordered a new keyboard. But of course they won't get the order until friday, so I'll probably be typing on the Backup Keyboard Of Pain for a week now.