Finnix version 86.1-pre1 has been released for x86 and PowerPC platforms today. Yes, you heard right. There is now a Finnix PowerPC ISO available for download. Documentation will be written by the time 86.1 final is released, but the short of it is:
G4s and Blue-and-White G3s (NewWorld) are well supported, and have been tested on about a dozen machines so far, including various G4 desktops, a few G4 laptops, Mac Minis, and a G3 iMac.
There is a G5 kernel in the distro (type “finnix64” at the boot prompt), but I do not have a G5 to test it on. Use at your own risk.
OldWorld G3s may work as well (using the BootX method), but will not be supported, and have not been tested.
There are also some other new features, which will be announced when 86.1 is final. Look at the changelog, download the ISOs, and let me know if anything comes up.