A few years ago, I was really interested in making a user-friendly desktop Linux to make 1996-2006 era non-x86 PCs usable as Internet terminals and for LibreOffice, etc.. There are plenty of PowerMacs floating around, but ideally you want to have separate builds for G3, G4, and G5. Does it matter enough that there are two variants of the G4 (7400 and 7450) to build two different sets of binaries for G4 and G4+? G3 doesn't have AltiVec, that's a big difference and incompatibility vs. later PPCs.