And then I was reminded that I probably did have a USB webcam lying around. And indeed, there was one sitting on top of the refridgerator. Didn't have XP drivers, but I got it working anyway, and it turns out to still be considered pretty high performance for video stuff (60fps!). Not great image quality, and the odd lighting of my living room seems to make its calibration a bit off, but.
Anyway, I'm not sure what I plan to do with it, but I'm amused at having a window open being able to watch me play with the computer in realtime.