I have my original 486 with VLB, to be honest it's a fecking awful bus. Limited number of cards, horrible to insert and remove, and almost completely absent on non x86 systems. I'd have no qualms using a PCI 486 system instead, provided the PCI implementation was solid.
I need to swap out the CL5428 in my 486 and replace it with something (probably an ET4000) that supports high colour in OS/2 1.3 whilst retaining DOS games compatibility.
Other builds :
I'm wondering if it's worth running something slower than a 486 (286?) for particularly old DOS games. I suspect not, turbo off is probably good enough.
Considered and rejected the idea of a CGA composite build - it's really neat, but there's only a few games worth playing (thanks for the feedback, everyone, though).
I'm definitely interested in a portable retro box, using a 486 based Thinkpad, and a Thinkpad Dock with a Soundblaster in it.
I'm pretty covered apart from the above. My three retro boxes are a 486 (old adventures/DOS games) which includes a Realmagic (yes, I bought it at the time new! (well, discounted end of line..)). The pentium ii has a Voodoo2, and an AWE64. My modern games box has an X Fi, an Aureal 2, and a Quadro that supports shutter glasses. I also have one of the Music Quest clones.
I am intrigued by early Mac gaming. I've a 733MHz Digital Audio Powermac that multi boots OS 9, OS X, Linux, OpenBSD, and NetBSD. That includes a Ti4600 flashed to support the Mac. If there are particularly old games that don't work in OS 9, it might be worth trying an older Mac (or possibly just using Basilisk).
I've a Roland CM32L, MT32, and Sound Canvas 55, so pretty covered on the sound front.
Sick bunny options :
I might get around to running a Token Ring network at some point, I have at least two ISA and two PCMCIA adapters, plus a (non active) MAU.
Also interested in a Nehalem system. I use virtualisation/vt-d, and want to compare vt-d in a Core2 system (doesn't support Second Level Address Translation), to vt-d in my new Sandy Bridge system, to Nehalem (first Intel CPU to support SLAT/EPT).
I've still got a dual P3 motherboard, and one 1GHz p3 processor, not sure of anything I can use it for. Also a P4 3GHz system, that's previously been used as a box for running BSD Unix. A socket 7 motherboard with a Cyrix MII 300 rounds it all off - I stopped using that because the CPU fan drove me crazy.
I fancy a relatively modern non Intel Unix system, so I'm likely to be grabbing a Mac Mini (slow, but quiet) and a Powermac G5 to run/develop BSD software in a big endian architecture. It'll be slow, but good enough.
Finally, sorely tempted at times by a Sparc system, but they're all really slow, hot, noisy, or all three. An SGI Fuel is tempting, but realistically I wouldn't use it (the O2s rarely get switched on as it is), and it's damned slow. Space is important, and noise is paramount.