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.

Voltaic Generator

Packing up to 15 watts in its included battery pack, the £499 Voltaic Generator can juice a laptop for roughly 5 hours. Plus, it's made almost entirely of recycled pop bottles. Looking for a more mainstream solar bag? Samsonite plans to release its own line of solar products this summer.

Voltaic Generator

Solar-powered camcorder

A search for green tech on Amazon turned up this 720p, 10X-optical-zoom camcorder fitted with two solar panels. Not a bad deal for $250, but fair warning: It's a no-name brand, and the product has no customer reviews on the site, and we can find it available only in the States. It's a nice concept, at least.

Solar-powered camcorder

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