At three pounds, this Toshiba is the lightest 13-inch laptop to have both a DVD drive and a full-voltage processor. To keep its 2.66-gigahertz Intel chip cool, vents on the side channel air directly over it and out the back. $1,600; toshiba.com
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.