The first idea is fairly boring and straight-forward. Take a normal case and give it a little extra width, and you're done! All the goods go on one side, the motherboard's back faces out and that's it.
Dissecting the case with the motherboard to put it on display is another thing entirely, though. Suddenly, there's a challenge in how small you can get the cube and still fit everything you need - a DVD drive, HDD and PSU get to be harder to fit. By the time you add multiple hard drives, card readers, LCD display and watercooling components, you get quite a challenge indeed.
It's this challenge that initially attracted Chris Cook (aka cc3d on our forums) to design and build "Phase III". First there was the cube, then the hinging lid, then hinged motherboard...the list just kept growing. What started as a cube ended up as a test bench on crack, and we're excited to bring you the worklog.
Check it out at Bit Tech.