Nearly 200 ,000 parabolic mirrors on the Mojave Desert make up Solar One, a power plant that focuses the sun's rays onto oil tubes, which boil water to power steam turbines that produce electricity. A Hydrogen fuel cell powers a prototype electric motorcycle. Go inside the fuel cell to learn how it makes power, and how it produces its only environmental emission: water. There's more to an escalator than we all thought. It processes and directs crowds while ongoing development keep us safe from injury. Ever wake up with a tattoo and wonder what happened the night before? Our inside scoop on how a tattoo machine works, may answer that. It stabs the skin 6,000 times a minute, as fast as the wings of hummingbird - only more painful.