The Sonea unit concept might look like some sort of ghetto blaster, but it gives back a portion of what it receives instead. This, ladies and gentlemen, is a machine that takes noise and convert it to energy for you to use it as you please. We’d probably think this would work best when installed at construction yards or somewhere super noisy, which would place it under the public domain and not for private use. 30 watts of power can be obtained for each decibel of sound it intercepts, which would translate to around 240kW of juice with each airplane taking off at the runway. We’d say that those figures are just theoretical, otherwise it would’ve been implemented by now.

via Sonea unit – Sonea unit harnesses power of sound.