Laser speckles could enable digital fingerprinting of paper

When it comes to digital fingerprinting, we've never thought about how the concept could be applied to paper. E-paper, sure. But the plain old dead-tree stuff? Turns out, with a powerful enough scanner,
a sheet of paper can reveal a unique "laser speckle," a pattern that is different on every piece of paper. Researchers are now speculating that low-cost scanners could be used to authenticate everything from passports to paper money by checking laser speckles, avoiding the need to introduce more expensive and controversial options like
RFID tags. Of course, laser speckles aren't quite as unique as fingerprints; researchers say the odds of two pieces of paper having the same speckle are about 1,000 to one. Seems like forgers armed with a few reams of paper and a scanner could hack together fake IDs that match real ones pretty easily, as long as they know what speckle they need to spoof.