I was going to dig out one of my old PCs to use when I set up my studio/dev room. I was thinking about my old dual Pentium Pro machine, then realised my last P3 would probably be better. Then I remembered... I saw a couple of P4 boards with ISA slots. This would be excellent!
I had a search, and found several interesting boards:
http://www.l-trondirect.com/aimb-741e-00a1.html (Advantech seem to have several)
I like the look of the MB-8650 personally. Has anyone ever used one of these?
I might do a little more research and put up a page listing all the boards I can find, if anyone would be interested.