"British defense company BAE Systems has developed an “invisibility cloak” that can effectively hide vehicles from view in the infra-red spectrum.
The patented system — called Adaptiv — uses a matrix of hexagonal “pixels” that can change their temperature very rapidly. On-board cameras sweep the area to pick up the background scenery and display that infra-red signature on the vehicle.
This allows even moving tanks to be effectively invisible in the infra-red spectrum, or mimic other objects. “The tank skin essentially becomes a big infra red TV,” BAE Head of External Communications Mike Sweeney told Wired.co.uk. “You can display anything you want on it — including a cow — while the rest of the vehicle blends into the background.”"
I can see using the idea, somewhat tweeked, in thrillers / suspense novels: an invisible spy, or the most obvious - a bank robber...