The NASA Institute for Advanced Concepts just awarded a phase 2 grant to research tiny hopping Mars robots. The robot looks like a 1" glass sphere with electronics inside and perhaps a swarm of these could research the whole surface of Mars! The little spheres jump like Mexican jumping beans by storing up artificial muscle energy and then boinking themselves up and away to the next location. These things are so tiny, they figure they can get about a thousand of these guys into the same sized container as the MER (Mars Exploration Rover). The swarm communicates on a node-to-node basis on a cellular communication network. With sensors, communication, and locomotion electronics all packed inside, that's quite a lot of stuff for a tiny 1" sphere!