Is Osama bin Laden sending coded messages in the pictures of goods for sale on EBay? Is that MP3 file carrying a secret note that tracks the listeners? Steganography is the art and science of hiding information in digital data and it stretches the boundaries of information theory and philosophy. An artful programmer can hide secret messages in such a way that a 1 is not always a 1 and a 0 is not always a 0. This talk will explore some of the popular schemes for inserting messages and discuss how they're used by hackers, poets, corporate bean counters, and programmers on a deadline.