MIT Media Lab researchers have created a new type of ID tag which is tamper-resistant and difficult to forge. The little tokens are composed of plastic embedded with hundreds of tiny glass spheres. The patterns created when a laser shines through are the key to the uniqueness of these devices. The patterns are captured by a digital camera and converted into a binary number. Recreating the spheres that results in that number is difficult and the uniqueness of the tokens comes from comparing patterns created by shining the lasers at specific angles. They are working on making the system practical, creating readers and viable applications. (via Wired News)