Think of cleaning up your hackerspace and find a reel of RGB SMD LEDs and coresponding drivers to controll them with some serial protocol. Thats what happend to us.
And think of having a factory nearby, where you can massproduce prints for a reasonable price, even better you can actually stop by and produce them. By yourself. Making stuff you know.
Our first Idea was to make some wierdshaped PCB, like a snake, e. coli or whatever. After brainstorming a lot, without having THE idea. Somebody had the idea to just threw some LEDs, take a picture, and arrange it in given way.
Well some beers and trys later, it's interesting how often randomly thrown SMD LEDS end up laying on a side, we had the first design. you can see it in the pictures.