Here’s a cool little project from 2011: procedurally generated pixel-art buildings for isometric games (Specifically OpenTTD in this case). Written by Richard Wheeler, the script builds the building layer by layer and then colors them.

This approach seems extensible to similar isometric art. It’s be fun to see if you could apply other common generative algoritms to producing pixel art like this.

Forum thread discussing its development: http://www.tt-forums.net/viewtopic.php?f=26&t=50932