The latest in emergent tiling; laid down at random on a floor of your choice, each double-sided tile will compare itself to its neighbours and flip itself over if it finds itself orthogonally adjacent to more than one of the same colour.

It might manage a perfect checkerboard eventually. Click the applet and press space to re-randomise them all.

(If you're wondering, a "flip over if adjacent to any of same colour" rule is doomed, because any clusters of checkerboard that successfully emerge are immediately consumed by doubt at the edges, and collapse in on themselves. Press 'z' to flip between this and the normal rule, to see for yourself.)

Implemented by Kevan with Processing, May 2004
(you can view the source)