• Two gigantic halves of a potato made from wood
• each half is equipped with oscillators, solar panels and real potatoes
• the solar panels provide the power for small speakers and amps
• the potatoes are part of the oscillator circuit and create some randomness of pitches and colours of sound

http://www.amazon.de/InnooTech-Ladeger%C3%A4t-Regenbest%C3%A4diges-Staubdichtes-Sto%C3%9Ffestes/dp/B015W3MTZS/ref=sr_1_3?ie=UTF8&qid=1458755360&sr=8-3&keywords=outdoor+solar+ladeger%C3%A4t

http://www.ebay.com/itm/Mighty-Max-12V-10AH-Wheelchair-Medical-Mobility-Battery-12V-Solar-Panel-/191577996157

http://www.ebay.com/itm/Solar-Panel-Charger-4000mAh-Rain-Shock-Dust-Resistant-Portable-Power-Bank-/321936059956?var=&hash=item4af4e26e34:m:m9hJlYcQVN7iKVPoBuj_3Ow