Stop wasting precious seconds pumping the air tank on your Supersoaker. Nerf's new compact water blaster is the first to have a battery-powered motorized pump, so you can soak your "friends" without ever having to stop to reload. $15 (available Spring 2011)
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.