PowerMac G3/450 with 1GB ram and 2TB external RAID (via eSATA/PCI SATA card) & PowerMac G4/500 with PCI SATA card, 250GB boot drive and 2x 3TB SATA drives.
G3 is my server and has 2x Gigabit NICs, while the G4 is a glorified 'NAS' and has one Gigabit NIC. Both of these Macs are headless. I access them via VNC screen sharing.
PowerMac G4 Quicksilver, 1.5GB ram, 1.8Ghz DP Sonnet Duet. PowerMac G5 2.3DC, PowerMac G5 Quad, 16GB Ram, PowerMac G5 2.7 DP.
17" PowerBook G4, 2GB ram, 128GB mSATA3 SSD.
PS: Are you aware of this forum on MacRumors?
Power Mac, PowerBook, iMac Gx, iBook, etc...
forums.macrumors.com