Researchers at Stanford and UC Berkeley have created an ultra-sensitive artificial skin, one that detected a fly and butterfly landing on it. When developed further, it could be used on prosthetics to allow people to "feel" what they're touching in a much more natural way than anything possible now. Also, of course, robots.
While it'll take some time to figure out how to make the skin interact properly with the human brain, it won't be as difficult to cover an entire robot in the stuff and have it "feel" much like we feel. It's just one more step towards robots being just like human beings, for better or worse.