Linux kernels have been ported as well, see http://nubus-pmac.sourceforge.net

On Mon, Jul 23, 2001 at 10:48:44PM -0400, John wrote:
> > As I am a Unix nut, Is there anything "unixy" that would run on these
> > machines - is it worth it to grab a couple, few?  Does anyone in the PA
> > area want any for anything?  Please let me know.  Thanks.
> 
> Some of the people in the port-macppc group are trying to get PowerPC 601s
> and NuBus-based PowerPC machines working in the NetBSD world.
> 
> Until they do, the only Unixy thing you can install right now is MkLinux
> (see MkLinux.org).