Little Drummer Bot

A very cool little robot posted on the Let's Make Robots site is the "Yellow Drum Machine". It's basically several motors, a microphone, two speakers, and a CPU glued on to a few pieces of wood. The sensors on the head also vaguely resemble "Johnny 5" from Short Circuit. The robot motors around and tries (based on the videos often fails) to avoid obstacles, and looks for a usable object or surface that it can drum on. When a suitable surface is found, the robot maneuvers into place, and plays a few beats against the surface. The beats are recorded by the microphone, and if the robot is "happy" with the results, it plays the recorded sample back and plays along with its own sample. It can also measure the tempo of stomping or clapping, and will join in after listening for four beats, and can incorporate shouting or singing into its rhythms. So far it doesn't seem to be much of a threat to professional drummers, so Lars Ulrich is unlikely to sue.

Video of the robot can be found at Gizmodo and Let's Make Robots.