"Scientists Create Cloak of Partial Invisibility":

Scientists have created a cloaking device that can reroute certain wavelengths of light, forcing them around objects like water flowing around boulders in a stream. To creatures or machines that see only in microwave light, the cloaked object would appear nearly invisible.

"The microwaves come in and are swept around the cloak and reconstructed on the other side while avoiding the interior region," said study team member David Smith at Duke University's Pratt School of Engineering. "So it looks as if they just passed through free space."