The aim of the floatable jellyfish-like vessels that drift around cities is to create temporary, ephemeral zones of privacy: an absence of phone calls, emails, sounds, smells and thermal patterns left behind by others. Through various electrical systems they are also able to prevent access of GPS devices, television broadcasts, wireless networks and other microwave emissions. Finally, by creating a "blurry barrier" and a ground-plane camouflage pattern, they provide shielding from the unembarrassed gaze of security cameras and surveillance satellites.

The vessels are powered mainly by sunlight and wind but are supplemented by inducted electricity from mobile phones and 802.11 networks (in crowded spaces this amounts to several dozen Watts of unexpended power). Buoyancy is achieved by heating or cooling air in a floatation sac, much like hot air balloons. The entire structure (total weight 4.1 kg) can collapse or expand as necessary to alter surface area in response to wind speed and altitude. The vessels have no particular destinations and drift like flotsam around the city. However, they must keep moving because to be discovered by the authorities means almost certain destruction.

source: haque.co.uk