For the past few years there has been quite a bit of progress toward using metamaterials to produce an invisibility cloak. Essentially, this involves using special materials to cause light to bend around an object instead of striking it. A team at the University of Dallas, however, has demonstrated invisibility using a different principle – creating an artificial mirage from sheets of carbon nanotubes. They already have a much larger cloak than can currently be built using metamaterials, and it can be rapidly switched off and on. This looks like it might be something with a lot of potential (even beyond the obvious military and espionage uses).