Well, they've done it. Researchers in China have built a mini 'black hole' capable of absorbing microwave frequencies, and they've done it without using the LHC (which many feared would cause a black hole to develop that would swallow the earth). The device they created, officially called a "omnidirectional electromagnetic absorber," is made of a thin cylindrical layer comprising of 60 concentric rings of metamaterial.
The research was published on June 3 in the New Journal of Physics and details how researchers manipulated the metamaterials which can distort light and other electromagnetic waves in the spectrum. The device, created by Qiang Cheng and Tie Jun Cui of the State Key Laboratory of Millimeter Waves at Southeast University in Nanjing, China, uses 60 strips of circuit board which is arranged in layers and is coated in copper. Each layer either resonates or does not resonate in electromagnetic waves based on their alternating pattern. It does this by spiraling the radiation inward and converts the energy into heat, just like a black hole does.
Currently, the device only works for microwave radiation, but researchers are planning for a device capable of absorbing waves in the visible light spectrum to follow.