Solar Blue Rays

Blue Ray is was an optical disc technology that was a bit denser than dvds but not that much.  Of course density is a function of the pit size and the imprinting pattern and it turns out that the pattern for imprinting blue ray disks makes a wonderful (Eli is tempted to say idea) stamp for visible light collection because of the good match to the wavelength of visible light.  Technical details can be found at Extreme Tech.   Folks at Northwestern have used this to raise the efficiency of solar cells by 20% or a bit more.  FWIW, they used Police Story 3 for their stamp.  Somebunny wanted it out of the house 

As IEEE Spectrum points out, the stamping technology is already available, and with the death of Blue Ray or at least its moribund status up for sale cheap.   The destructive creativity of the market at work.