Scientists at the Department of Energy's Argonne National Laboratory are talking up a type of millimeter-sized microbots that can swim and use their "jaws" to move around objects multiple times their own weight. The tiny 'bots are made up of microparticles and don't do much on their own, but once magnets are applied, they form star shapes and swim around, even opening and closing to push around non-magnetic objects. The "asters," as they're known, will also reshuffle their parts, if they lose any particles, effectively reassembling themselves. Videos of tiny robot dance numbers after the break.