Cloak of invisibility
BBC News: Experts create invisibility cloak.
A US-British team of scientists has successfully tested a cloak of invisibility in the laboratory. The device hid a small copper cylinder from passing microwaves in tests at Duke University in North Carolina. It works by deflecting the microwaves around the object and restoring them on the other side, as if they had passed through empty space. But making an object vanish before a person's eyes is still the stuff of science fiction - for now. The cloak consists of 10 fibreglass rings covered with copper elements. This is classed as a "metamaterial" - an artificial composite that can be engineered to produce a desired change in the direction of electromagnetic waves.
The cylinder was only invisible to microwaves, doing this with visible light isn't possible yet. But it could be done with radar with some work.