Ready for another Mars robot? No? Too bad. NASA scientists are working on a pyramid-like robot called the TETwalker (which stands for "tetrahedral walker") where each side of the pyramid is actually an expandable strut. There are no wheels, so to move around the each point on the tetrahedron sports an electric motor which can expand or contract the struts, raising the center of gravity of the bot just enough for it to topple over in the direction it wants to move. The TETwalker just repeats that action over and over again to get around. We're probably missing something, since this sounds like an incredibly inefficient way to make your way around Mars (how would you move uphill?), but the researchers working on this say the plan is to miniaturize the TETwalker and then have scores of them roaming the surface of Mars in "autonomous nanotechnology swarms", or ANTS (damn you scientists and your clever acronyms!), that can change shape to adapt to different circumstances and tasks.