Satellite radio's one great drawback is that it tethers you to your car or home. But with the palm-size MyFi, you can take your programming anywhere. The 7.3-ounce player receives live broadcasts and stores at least five hours of recorded programming on its 128 megabytes of internal memory. So if your signal drops when you go inside, you can continue listening. $300
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.