POWER5/6 systems are pretty much commodity systems, and there you can do weighted sharing of CPU time between LPARs with a guaranteed minimum. Some of the low end boxes are pretty competitive to similarly configured Intel/AMD boxes, tho it varies a lot with memory/disk configs.

But for virtualization work where SLAs are involved, it might be something to at least consider.

Yup, it was true. Played it on OS/2 with a Matrox Mystique video card. Why OS/2? Because it had native OpenGL and IPX support... it was built for Quake, multigaming with IPX and OpenGL goodness :)