I just now caught your series today on MacSurfer. I've been working on a media server utilizing and old G4 sawtooth PM. I do have an Apple TV because we have a few Macs in the house. We also have family visiting with their Macs who have access to the ATV.
I'm anxious to see how you "automate" things.
I began upgrading my AGP/Gigabit G4 a number of years and this is how it sits today.
1. 1GHz OWC processor (stock 400MHz)
2. 2GB OWC memory
3. Radeon 8500 AGP Mac 64MB vram
4. Radeon 7000 PCI Mac 32MB (was dual monitor, not now)
5. Pioneer DVR-109 Superdrive
6. 4-port SATA PCI card
7. Four 400 GB SATA Seagate Barracuda drives (raid using OSX)
6. Airport Card 802.11b, now hooked directly into the Airport Base Station Extreme "n" using ethernet.
7. Video/Audio Software: iTunes, Quicktime Pro, VisualHub, Handbrake, Fairmount, Drop2DV, Tivo DecodeManager, iMovie and Final Cut Express.
Building a PowerMac Media Center Part 4: What Applications You Need