I have it running off of my Wallstreet 266 with 128RAM. I think it is actually a supported machine by apple's definition. Any PowerBook G3 except for the original one talks about the first "PowerBook G3"not the "powerBook G3 Series" The "PowerBook G3" has an appearance much more like the powerbook 5300 or 1400 or 3400. The "PowerBook g3 series" is the one with the crystal logo on the lid. these are supported goto:
MacBoy is close - By "original Powerbook G3" they mean the "Kanga" series of Powerbook G3 - the G3/250 in the same case as the Powerbook 3400. Not really sure how many of those are around, but my girlfriend has one. (I've got the G3/266 Wallstreet, OS X runs pretty good on it)
I installed OS X PB on my wallstreet 1 (233 w/out bs cache) just fine. Supported machine, as they should be as they're native G3's.
Runs remarkably well considering it's such a slow CPU and lacks l2 cache.