This is too cool. The "Tilted Twister" is a robot, built from Legos, that solves Rubik's cube, with no external PC. It was built with standard Lego Mindstorms NXT kit.

You need to see it in action to appreciate it. First, it scans all the sizes and determines the colors the cube has. Then it begins twisting sides:

More info on the Tilted Twister page to the video.

From: Tilted Twister, via Hackzine.