<p>You can't be 'leet if you can't do crypto. There was a time when the difference between good crypto and bad crypto was life and death. Until the advent of modern computing, cryptography was done by hand, sometimes by candlelight by a spy in an attic surrounded by Nazis in occupied France. Today there are at least 2,381 crypto downloads at sourceforge.net, but good crypto is like a good joke -- someone clever had to start it.We'll look at how early crypto formed the foundation for secure communications, and why the discovery of asymmetric crypto is the real reason the Internet got so big so quickly. We'll walk through some crypto contests of the past couple of years, including Shmoocon 2008 and Shmoocon 2009 (as well as the Shmoocon 2009 badge puzzle), and provide you with the foundational understanding of how good crypto works, and why bad crypto fails miserably. You might not become the next Phil Zimmerman by watching this talk, but you will be able to do some pretty cool stuff.</p>