This is just strange. This just recently appeared on /. and you find some discussion there. Apparently there will be a webcast as well.
Maybe May 4th will be a slow night on TV and you will want to participate in what I can only categorize as weird science.
Sky Ear will be a one-night event in which a glowing “cloud” of mobile phones and helium balloons is released into the air so that people can dial into the cloud and listen to the sounds of the sky.
The cloud will be made of one thousand large helium balloons each responding to the electromagnetic environment (created by distant storms, mobile phones, police and ambulance radios, television broadcasts, etc.) with coloured blue, red and yellow lights.

Methinks that the most likely things you’ll hear are cell phones ringing.
> Methinks that the most likely things you’ll hear are cell phones ringing
eheheh… or just the wind 😉
I really hope someone brings a BB gun…
“Can you hear me now?”
I’ll be there! I’m intrigued with the notion that the balloons will change colour as they rise from the ground in response to changes in electromagnetic radiation around them. Will they be sensitive to radiation per se or simply that detected by the phones linked to the balloons?