MorpHex Hexapod Ball
Norwegian engineer Kare Halvorsen created an hexapod robot called MorpHex capable of transforming itself into a ball and rolling (transformer robot).
Currently not perfectly round shape of the robot (asymmetrical sphere, flat at the poles like the Earth) does not allow it to roll like a ball, but it’s planned for the next update.
Kare participates in a contest to win $ 10 000 or a Makerbot 3D printer. If you like the DIY concept below, you can help him by voting at this URL.