It was actually reasonably easy to assemble one yourself. A company I worked for bought a bunch of motherboards with 21164 (EV56) CPU's. I took one home, and was surprised to find at the time it was reasonably easy to get it into an ATX case, install RAM, CPU and Debian on it.

I have fond memories of building Gnome 1.x from sources on it. It felt really fast compared to the Pentium 2 and 3's of the day.