Today, more than 40 Darpa-backed companies and academic labs are developing robots. There are recon machines that can be air-dropped into enemy territory and relay back intelligence data in real time. There are 3-pound surveillance bots that frontline soldiers could lob through a window or around a corner to get an audio and video preview of conditions. There are robots that can negotiate harsh terrain, scurry up stairs, or rush into battle to rescue injured soldiers pinned down by heavy shelling or gunfire. Other machines in development can carry weapons, deliver jolts of electricity, sniff for biogerms, and see through walls. Also see SAIC’s Throwbot.