Metamaterials make it possible to bend light in a way that could make an object nearly invisible. There are many obvious applications for such a material but until now most metamaterials were not able to be created big enough for any grand purpose. However with the advent of printable metamaterials we may soon have invisibility cloaks.
Until now, most metamaterials have been painstakingly etched out of metal sheets by electron beams, and the biggest pieces able to screw with visible light have topped out at about 100 micrometers or so, about the size of a human hair. A group from the University of Illinois has figured out a way to create a "stamp" of sorts that can repeatedly create pieces of metamaterial several inches on a size, and it should be easy to scale that up into square feet. With this much metamaterial, the first applications could include infrared cloaking devices and optical superlenses.