This is a great topic line; I'm surprised there hasn't been more takers.
My ultimate computer plan is to rule the world with 486 clusters... just kidding.
I did have some lingering desire to find a fast PCI-based socket 3 system with PS/2 ports and working support for 1024 KB of cache. I've tested a lot of socket 3 boards in the past 15 years and am edging towards the conclusion that such a board does not exist. There is 1 board left out there for me to test which has potential, but I haven't been able to find it for the right price. Even boards which supposedly support up to 1024KB of L2 cache have turned out to be flaky.
Other than that, I'm fairly satisfied with my existing retro systems (in retro cases),
• Cyrix 5x86-133 @ 33 MHz FSB, PS/2, 512KB cache, 3 PCI
• Cyrix 5x86-133 @ 66 MHz FSB, PS/2, 512KB cache, 3 PCI
• Dual Pentium 850 MHz (Slot 1), 1 GB buffered ECC RAM (Dell Precision Workstation)
• Dual Pentium Tualatin 1400 MHz, 4 GB ECC RAM, 2 PCI-X, 4 PCI (Intel SAI2)
• Pentium 1 GHz (Slot 1) @100 MHz FSB (Asus P3V4X)
• Cyrix 386-40, 16 MB RAM
• Macintosh SE/30, 32 MB RAM, Mac OS 7.5.5
In a way, the Cyrix 5x86-133 @ 66 MHz FSB runs the RAM so fast, it is as if having the cache is no bid deal even if you up the RAM to 256 MB, that is, since the RAM is running double speed anyway, there is no need to get greedy with having all your RAM cached. It is sorta like having a Cyrix 5x86-133 @ 33 MHz FSB w/1024 KB WB cache and 128 MB RAM, whereby all the RAM is cacheable.
As for my other eventual plans, I'd like to find another AT case to plop in a socket 7 motherboard and add this to my KVM w/audio setup. I have the motherboards, just need a decent looking AT case from 1996-1998. I'd also like to create the Ultimate Socket 7 Benchmark Comparison at some point, which would be analogous to the Ultimate 486 Benchmark Comparison.