Greenwich Park's sky to be turned into RF-driven balloon-art

Rupert sez, "On May 4th, above the Greenwich Meridian in Greenwich Park, London, a cloud of a thousand radio-sensitive glowing balloons will monitor the airwaves and respond by changing colour and brightness. Everyone's invited to bring their mobile phones and make contact with the cloud, which will also listen to atmospheric phenomena and the cackle of the rest of London's radio users."

Link

(Thanks, Rupert!)