Hate having the guy next to you in a movie theatre chat about everything and nothing right at the climax of the movie? Engineers at Japan's Iwate University have developped a wall which would block the cellphone frequency band.
Oka is developing wall paneling that absorbs microwave signals, rendering cellphones useless. The paneling is made from two sheets of ordinary fiberboard that sandwich a third layer made of nickel-zinc ferrite powder and a binding compound. Electromagnetic waves transmitted by cellphones are absorbed by the ferrite particles and converted to small amounts of heat. The fact that they are absorbed rather than jammed is key, as the jamming of radio signals is illegal in many countries, including the United States.More information @ Popular Science