Well they are getting there…
IT BEGAN as just a wizard idea from a British scientist. Yesterday it became a reality.
And reality began to disappear.
Following in the footsteps of Harry Potter, it was revealed that the world’s first invisibility cloak has been tested in America. So far the device is rather limited — it is 5in (13cm) wide and can hide an object only from microwave beams.
But the principle established by Sir John Pendry, a professor at Imperial College, London, has been proved to work and in the next five years there are hopes that total invisibility may become possible for larger objects. Tanks, for example.
http://www.timesonline.co.uk/article/0,,2-2412995,00.html
…. and peeping toms.