C-One Reconfigurable Computer.

Want an Amiga, Vic-20, C64 and a CPC464? Why not save space and get one of these from Jens Schoenfeld. It's not cheap, you still need to get an ATX case etc to house it and it's still just a development board (one of the original creators left this project to create the C64 DTV) but 4 in 1 isn't bad.

That site is already existing for over 5 years. I already wanted to get one at that time, but I thought it was too expensive, considering what I'll do with it.