Very cool new military technology by BAE Systems called Adaptiv--it's an invisibility cloak (yes, we now have the technology of the Klingon Empire at our disposal!)
Hexagonal pixel plates are affixed to tanks (and soon battle ships) and these can change temperatures to be invisible to infra-red sensors and confuse heat seeking missiles.
Moreover, onboard cameras pick up surrounding scenarios and can display this onto the vehicle's pixels, so that the military vehicles blend right into their environs.
Another trick, is that that the pixels can display alternate images to masquerade itself-- so a tank is now a simple car or even a cow (according to Wired UK, 6 Sept 2011).
Like the Trojan Horse, I can only imagine what a military power could do by fully exploiting this capability--whether through the conduct of hit and run maneuvers or by invading and conquering an unsuspecting foe.
This is the emergence of a whole new era of war-fighting capabilities, where camouflage is no longer just covering yourself with the basic elements, but rather where technology is used to create a virtual reality that masks the true physical.
On the battlefield, this technology will enable us to seemingly be there one minute, and gone the next (machines and people)--that's technology magic that even Houdini would be envious of.
And yet, this is still just the beginning...we are only now bordering on the capabilities inherent in the Star Trek holodeck--where whole alternate environments are just a simulation away.