In development, a microwave camera that can see through clothes, etc., for security. The only problem I have is with the microwave emitter it requires, especially for long exposures.

New Metamaterial Camera Has Super-Fast Microwave Vision

A small, microwave-detecting camera that can see through solid materials in real time has been developed. Soon, the device could be adapted and used in law enforcement and security where, among other uses, its inventors envision airport scanners that screen passengers for weapons or explosives as they walk by.

The camera features a one-dimensional aperture made from a copper-based metamaterial.

... scientists used the copper-based metamaterial as an aperture for microwaves,... By connecting the aperture to an image-reconstructing computer, the researchers can capture information from a scene in real time, with no moving parts.

In the current study, researchers aimed the camera at a room that had been muffled by microwave-absorbing foams on the walls and ceiling – and then studded with bright metal objects — “Little balls, basically,” Hunt said.

After turning on a nearby microwave transmitter, the team watched as the metamaterial aperture shunted microwaves bounced around by the metallic objects to the computer, which created a two-dimensional reconstruction of the scene.