The Nanjing Mantle

The Nanjing Mantle, developed by physicist Yijun Feng, is the first working prototype of an invisibility cloak.  Using layers of metal rings 40 nanometers across, it bends light around the jacket and back again to create invisibility.  It has both an active and an inactive state. It was stolen from custody of the Smithsonian in 2009, current whereabouts unknown.
The invisibility gear worn by the marines in Escape from Petropolis is based on the same technology.