The electronics revolution shows no signs of slowing down. When I was a youngster we had dial telephones, AM radio, and black & white TV with a tall antenna on the roof. We did not have microwave ovens, cell phones, computers, FM radio, or GPS systems and there were no satellites. Well hang onto your hats, because the revolution has just begun...X-ray vision is already here... sort of.Knowing that radio waves can pass through solid materials, in 2006, engineers at Cambridge Consultants in the UK announced they had built a device they called the Prism 200 which can detect people through a brick wall. The briefcase-sized system works by transmitting pulses of ultrawide-band radar and listening for returning echoes.According to the company, these pulses can pass through building walls over 16 inches thick, and detect human beings behind those walls over a range of up to 50 feet. The device can only detect people when they are moving.Erwin Biebl's radar sensor. Biebl's team at the Technical University of Munich in Germany has built a device that can pick up tiny motions like breathing, or even a beating heart, through a closed