I'm really sorry but do what zenstate said. That is sacralige. lol j/p. But why not just use a cool regular atx case, thermaltake makes a nice one thats aluminum, and I think lian li makes a nice g5 wannabee case.
Mobile-2.2Ghtz Core 2 Macbook, 4GB ram, 160GB HDD
Server-Dual 1.42 MDD G4, 1GB ram, 4 random hard drives.
PC-C2D 2.4Ghtz, Asus Commando, 2Gb ram, 3 hdd's in raid 5, 8800GTS.