She (he? who knows, at this age) wandered into an acquaintance's bedroom. The acquaintance's cat has disclaimed all responsibility, and no obvious chick-emitting sources were found nearby. The chick-finder will continue investigation, but in the meantime we have appropriate food and cat-free shelter, which she does not, so until further notice we've got another chick.
She's a pretty thing, kind of a dark gold, a bit redder than Galen, with some darker speckles on the wings. She's drunk and pooped, and probably eaten (Cathy gave her some food before I got home, and it's been scattered about), so seems to be in good health.
Huzzah, chickens. Once I get a picture I'll see if anybody on Backyard Chickens can identify the breed in case that helps track down the owner.
 Trains are big! Trains are mean! Do not taunt happy fun train and stay off the damn tracks, you guys.