A couple of years ago, Maximilian Kern created a bipedal robot controlled by a microcontroller. Building on that experience, he has released into the Thingiverse a small Canbot that uses an Atmel Attiny85 microcontroller to direct it's rolling gait through space. Inspired by the iPhone controlled Ollie robot, the Canbot is controlled by a modified TV remote and fully equipped with ultrasonic sensors to keep it from mindlessly banging into things when left on its own. Check out more details about the 3D printed Attiny Canbot in the full story: http://3dprint.com/90065/3d-printed-attiny-canbot/