I recently managed to build a miniature AT-style case for 4DPS socket 3 mainboard, but I decided to upgrade it and put something more powerful there, so I created a Super Socket 7 system 😀

Here it is compared to a 24 inch monitor and a speaker.

Here are some topics about building the case itself:
Re: DIY retro PC case projects
Little Voodoo (cardboard) Box [P1] + 486 with small DIY AT case

That case is measuring only 28 x 13,8 x 22cm, it has a form of a really miniature AT tower with laptop-style CD drive and 3,5" floppy drive, custom-made microcontroller driven MHz display and reset, turbo and power button. I am using pico-atx style power supply (that mainboard accepts ATX power), which requires 12V input from a regular brick-type power supply.

Specs:

Super Socket 7 mainboard, AT, small form factor, no signs of brand name, identified only by BIOS string (here is manual http://support.pcpartner.com/support/man/via/895400.pdf).
It has MVP3 chipset and the CPU voltage can be set from 1.8V.

K6-2 500 MHz CPU - i will replace that with K6-2+ I ordered from ebay, should generate less heat and save some power.

Voodoo Banshee 16MB AGP

Sound Blaster AWE64 Value

PCI WiFi card

64MB RAM (i can add more of coure, will replace that with 128MB)

DVD slim drive

20GB laptop HDD drive (Hitachi Travelstar, very quiet)

FDD

Turbo button connected to multiplier selection - allows choosing 250 or 500 MHz. Restart required. It can also be connected to FSB selection, but mainboard crashes after reboot so full power-down is required. In fact, turbo buttons weren't popular in PCs made in that time, but a MHz display looks cool 😀

I probably should make some cables shorter because it looks pretty messy inside, also the back side could be covered with something, but anyway it is a complete system now, which can take regular extension cards like a typical tower, but it is so small that it can stand on the desk, next to the monitor 😉

You can see on the photos that it is not much larger than a Windows 3.11 box. I think that such a small tower is even better solution than a desktop-style case. I am using it with a KVM switch, when it's not needed it can be unplugged and placed on a shelf very quickly.