I've got at least one of almost
every early box SGI produced: PI, Indigo, Indigo2, Indy, O2, Octane, Octane2,
Crimson, Onyx RE2, Onyx IR
Hopefully someone will save examples of the 4D series and the software
for them.
I think there are still a few of the 68k machines around (though probably
none the earliest of the 1xxx series with CPUs based on the SUN design.
It may be time to put up the docs on the 68K machines that I've had buried
in storage along with a copy of the SGI 68K FAQ I helped with years ago.