Although most places (yours included) state that PowerMacs without Open
Firmware won't run any *nix-type OS besides MkLinux I have Yellow Dog
2.3 running on a 6100. I'm planning to use it to learn Linux and such.
Currently I know how to turn it on, and I know how to shut it down.
Exciting...

There are roughly 2 or 3 sites that talk about how to do it, and in any
case rely on NuBus-enabled kernels written by someone not affiliated
with any of the distros (which would explain why only MkLinux tends to
get mentioned.)

The other distro I believe to be available is Debian, although you won't
find it mentioned on their site either. Perhaps someone with the
knowledge and interest could at least modify the YDL or Debian kernels
for other OSes.

Just wondering if interest in the NuBus Macs come up much, given that
they should be a little more desireable than the 68k models, and
probably more available.

-David