I used Lego's Digital Designer software to build a model of a Sinclair ZX81 — the computer that kicked me off on my interest in such matters way back in 1981. Until very recently, the software allowed you to upload your model, buy it and get a boxed set with all the pieces to build it (as well as instructions). The ZX81 model is as close to the shape of the original as I could make it, considering that Lego is quite a lo-resolution modelling tool. I even made it so that you can lift off the lid and see a representation of the PCB in side. I have also posted the model to Lego's Cuusoo site — a place where you can post ideas, and if they gain enough support they will be considered for production.

http://idle.slashdot.org/story/12/01...de-out-of-lego