Computer scientists at the Columbia University School of Engineering and Applied Science have invented FontCode, a new way to embed hidden information in ordinary text by imperceptibly changing, or perturbing, the shapes of fonts in text. While having obvious advantages for spies, FontCode has perhaps more practical application for companies wanting to prevent document tampering or protect copyrights, and for retailers and artists wanting to embed QR codes and other metadata without altering the look or layout of a document.