Very cool! When I was in school, we still had a few G4 sawtooth's floating around with OS 9 being used as video editing machines for my multimedia class. They did OK for basic needs, but they didn't have much hard drive space (then again, none of the macs did because nobody knew how to delete stuff when they were done with it ).

I've used thumb drives on many Macs with OS 9 and never had any problems. Not sure about other drives, though. The only thing (if I remember correctly) it adds random files to your thumb drive like "TheVolumeSettingsFolder"... and it seems to make various copies in different folders. It gets annoying sometimes if you use a thumb drive that you have a lot of stuff on. Not sure if theres a way to prevent it, I just got used to it.