Neal Krawetz, PhD, has been active in the security community for more than 15 years. He is skilled in computer forensics, profiling, cryptography and cryptanalysis, artificial intelligence, and software solutions, and often assists law enforcement. Neal enjoys a novel hobby—he collects operating systems. He's currently running RedHat, Ubuntu, Mac OS X, OpenBSD, Microsoft Windows, OS/2, Solaris, and HP-UX, among others.