Every time this client goes to a campus printing station, she can't help but notice how much "good on one side" (G.O.O.S) paper gets tossed into the recycling bin.... She often finds herself picking through the bins and pulling out all the pieces that still have a good side and bringing them back to her office to use as scrap paper. We can't help but wonder how much G.O.O.S paper never gets rescued :-) 
The need is to design a machine that sifts through paper that gets tossed into recycling, detects which sheets have a full ‘good side’ and pulls them out, leaving behind those that have something on both sides.