So, the beige G3 300 arrived. And so did woe.
Well, it's not quite that bad. The thing is that I'd wanted to set the machine up standalone, so it wouldn't need MacOS. Unfortunately I've been unable to get Open Firmware to boot quik at startup time. So, I've had to resort to booting into MacOS and then quickly dropping back to Linux via BootX.
Everything else about the Debian PowerPC installation went just fine, fine. I'm a bit disappointed that I can't currently keep the box running without proprietary software though. I described my woes to the debian-powerpc list, but I'm not so hopeful of finding a way out.
Hardware-wise, I like the box. It's very easy to get inside and add or remove devices. I've got a USB PCI card and a Firewire PCI card inside it. They're working with kernel 2.4.19-rc3 just fine.
Maybe, if I close my eyes and wish hard enough, someone will know how to make it boot from Open Firmware. Just maybe.