So, not only did it allow me to copy off all of my files, it sorta kinda still works, too. Maybe. I haven't really pushed it, though, and right now, it's doing a full suite of disk checks on itself before I try any new tricks with it.
Either way, I no longer trust the drive, so I'll probably be ordering a bigger one Monday, when I gets paid again and I'm not worried about potentially bottoming out the bank account (hard to say, on that point, given that I don't have access to Quicken at this exact moment, what with it doing the full disk checks and all. I think I'd be okay right now, but...) I'll probably grab one for my Mac, too, since 120GB 2.5" drives seem to run for pretty cheap these days, and it looks like you can get a 2.5" external enclosure with USB for $10 or so. Which even makes it practical.
Annoying that I'm spending the money on this right now, but it could be a lot worse.
Considering the horrendous crunching noises the disk made last night, though, it's pretty astounding that the sucker's doing anything right now.