Every day is Earth Day, hard-core environmentalists will tell you, but on the calendar it's April 22. And if you want to show some support for Mother Earth, you might as well do so without abandoning your techie principles. There's no shortage of energy-efficient, ecofriendly, or generally "green" gadgets available, but here are 15 of the coolest, weirdest, and most practical, in no particular order.
The Energy Detective
What good is all this energy-saving gear if you can't measure how much of a difference it makes? The Energy Detective connects to your breaker panel and transfers data to a wireless transmitter connected to a wall outlet, which then sends the information to the gadgets pictured here. TED also connects with Google PowerMeter, a free web app for tracking home energy use.