Here's a cool little robot guy who rides a bike. Is it cheating when they only make the robot 50cm tall to ride a little bike? Even at that height, managing gyros and balances to get a robot to stay on two wheels is pretty clever stuff. He can even handle bumps in the road too, plus detect obstacles and avoid them. Go, Murato Boy, Go!
Extra points for the downloadable papercraft version of Murata Boy, so you can have your very own cool little guy on your desk.