Relatives who showed up today delivered unannounced devices!
This #PowerMacintosh G3 desktop looks, from the outside, to be in good shape. It even came with a keyboard and two mice, and the "getting started" box. No idea where the optical drive went, though.
Update: there's a DVD drive! It's just pitch black and recessed far back into the case.
I'm not going to even connect a power lead until I open it up and check the motherboard. Fingers crossed.