Sandia - Mini-Robots
At 1/4 cubic inch and weighing less than an ounce, it is possibly the smallest autonomous untethered robot ever created. Powered by three watch batteries, it rides on track wheels and consists of an 8K ROM processor, temperature sensor, and two motors that drive the wheels. Enhancements being considered include a miniature camera, microphone, communication device, and chemical micro-sensor.
see article here
