High-tech paint locks out unwanted cellphone signals on demand

Playing to the backlash against ubiquitous communication, a company called Natural Nano is developing a special high-tech paint that locks out unwanted cell phone signals on demand. Newsday reports.

"NaturalNano has found a way to use nanotechnology to blend particles of copper into paint that can be brushed onto walls and effectively deflect radio signals.

NaturalNano will combine this signal-blocking paint scheme with a radio-filtering device that collects phone signals from outside a shielded space, allowing certain transmissions to proceed while blocking others.

It appears to be legal - jamming devices that emit radio signals to prevent cell phones are not - The radio filter would allow all emergency radio communications to pass through the shield With all other signals, like cell phones, the filter would act like a spigot to block or allow them to pass through—say, only during intermission."