The other thing is that the 9100 is incredibly simple.
Seriously. HP
pulled all sorts of tricks to reduce the component count, not all of
which would be applicable to other designs.
Not only did they pull all the tricks, but they made a very nice product
in the end, too.
Gees, there was this other HP engineer famous for low component counts,
started this computer company in the 70's when HP decided they weren't
interested in his ideas. I think the guy goes by the name Wozniak and
for some reason I believe Apple is still around :-).
Tim.