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Physicists in the US have made the first ultrathin flat lens. Thanks to its flatness, the device eliminates optical aberrations that occur in conventional lenses with spherical surfaces. As a result, the focusing power of the lens also approaches the ultimate physical limit set by the laws of diffraction.

Really nice indeed! The new flat ultrathin lens is different in that it is a nanostructured "metasurface" made of optically thin beam-shaping elements called optical antennas, which are separated by distances shorter than the wavelength of the light they are designed to focus. These antennas are wavelength-scale metallic elements that introduce a slight phase delay in a light ray that scatters off them. The metasurface can be tuned for specific wavelengths of light by simply changing the size, angle and spacing between the nanoantennas. "The antenna is nothing more than a resonator that stores light and then releases it after a short time delay," Capasso says. "This delay changes the direction of the light in the same way that a thick glass lens would." The lens surface is patterned with antennas of different shapes and sizes that are oriented in different directions. This causes the phase delays to be radially distributed around the lens so that light rays are increasingly refracted further away from the centre, something that has the effect of focusing the incident light to a precise point.

Biomimetic Gradient Index Lenses - from fish

might look a bit scary ...

Cheap and scalable invisibility cloaks being developed. The setup is so trivial that I would almost call it a "trick" (as in "Magicians trick"): 6 prisms of n=1.78 glass. Nontheless, it does the job of cloaking an object at visible wavelengths and from several directions.

Is this really new? I don't know, but I know that the original idea of cloaking was pretty different. When cloaking as an application of transformation optics became popular people tried to make devices that work for any incidence angle, any polarization and in full wave optics (not just ray approximation). This is really hard to achieve and I guess that the people that tried to make such devices knew exactly that the task becomes almost trivial by dropping at least two of the three conditions above.

I think it is very easy to call something trivial when you're not the one who invested considerable time (5 min in my case) to design a cloaking device and fill the coffee mugs with water... Also, I did not really violate that many conditions: true I reduced the number of dimensions in which the device works to 1 (as opposed to the 2 dimensions of many metamaterial cloaks). However the polarization should not be affected in my setup as well as the wave phase and wave vector (so it works in full wave optics) - apart maybe from the imperfect lens distortion, but hey I was improvising.

High energy gamma rays are shown to be bent slightly by specialized lenses. The effect is likely due to pair-creation close to the atomic nuclei in the material.

"V3Solar has developed a cone-shaped solar energy harvester that is claimed to generate over 20 times more electricity than a flat panel thanks to a combination of concentrating lenses, dynamic spin, conical shape, and advanced electronics."

Hmm.. that seems counter intuitive... how would it ever be that much better than a flat panel? Rotating the PV will only make sure only parts are illuminated. Operating temperature is a better argument, but that comes at the cost of exposure. Came across this little gem of a webpage, maybe we should outsource our impossibility EM drive work next time? :) https://www.metabunk.org/debunked-v3solars-spinning-solar-panel-cone-spin-cell-coolspin.t1166/

would I still be allowed to close my eyes???

I guess so, but I dunno if it would help with those: http://www.engadget.com/2008/01/17/researchers-put-circuits-on-contact-lenses-freak-out-rabbits/