I ordered one of these a few days ago to be a temporary main machine for 6 months or so. It’s the predecessor to the Mac Mini, a G4 Power Mac Cube. It’s 8″ X 8″ X 10″. I can upgrade the processor, but it’s got 768 meg and a 120 gig drive. That’s close to enough for 10.4. I’m excited. The Mac Mini I’m on now is just underpowered for what I’m doing. This should be better and later I can use it around the house to play music or something off the network shared iTunes.
I also ordered a G4 Power Mac to use as a file server. All the USB drives can connect to that and it will be a constantly running file server. It was $180 for an old G4/466 with 4 PCI slots.