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Top 5 Green Gadgets


2
Griffin AirCurve
Griffin's AirCurve uses no power but still manages to amplify sound 10 decibels.
Griffin's AirCurve uses no power but still manages to amplify sound 10 decibels.
Griffin Technology

Here we go again, breaking our own rules. The Griffin AirCurve is made out of a polycarbonate, meaning a plastic. But it earns its green stripes by acting as a speaker that uses no electricity.

It's more accurate to call the AirCurve an amplifier. It takes the sound from the built-in speakers of an iPhone and amplifies it an impressive 10 decibels [source: Griffin]. There's also an incorporated slot through which you can slide a cable to keep your iPhone charged. The result may not appeal to audiophiles, but for basic users, the $20 AirCurve is a cheap, energy-free method of turning your iPhone into a mini-boom box. One reviewer pointed out that it might be more useful for amplifying podcasts or if you use your iPhone as an alarm clock [source: Kriegel].

How does it do it? The AirCurve's elegant design features a "horn" whose sinuous form may remind you of a seashell. (Think about how holding a conch shell to your ear amplifies the sound contained in your ear.) The shape of this "coiled waveguide horn" -- as Griffin calls it -- manipulates incoming sounds so that they are amplified when they come out on the other end.