If you've got 'Green Voice' and an empty bottle, then you've got yourself a speaker. This speaker makes use of empty bottles and containers, turning them into eco-friendly sound systems.
'Green Voice' was designed by Nien-An Lin, Ya-Fang Cheng and Genius KYE Systems Corp, and is made out of biodegradable material. What I find most interesting about 'Green Voice' is its battery. The battery is said to be a "paper battery," which both intrigues and confuses me. Either way, I can't wait for the day when my empty water bottle can also double as a speaker. No more refills for me.