I was reminded of Substrate [1], which spawned mrdoob's version [2] and led to a WebGL 3D version [3]

[1] http://www.complexification.net/gallery/machines/substrate/i...

[2] http://jsdo.it/mrdoob/xI3u/fullscreen

[3] http://www.jabtunes.com/labs/boidsnbuildings/