I audited this class (just showed up on the first day of class, not an MIT student, not registered). This class is probably the best class I've ever taken. I we

I audited this class (just showed up on the first day of class, not an MIT student, not registered). This class is probably the best class I've ever taken. I went from knowing a little about cryptography and computer security to doing novel computer science research (as one of the problem sets I broke a SHA3 candidate http://ethanheilman.tumblr.com/post/16944272296/shash http://ethanheilman.tumblr.com/post/16944272296/shash ). It isn't particularity "heavy and hard into cryptography", but it is very hands-on with many programming problem sets and puzzles to solve. It covers security from AES to secure voting to firewalls to buffer overflows to sql injection to physical security. This class will teach you to build more secure systems. To get a good idea of what the class is like check out the lecture list. http://courses.csail.mit.edu/6.857/2012/handouts http://courses.csail.mit.edu/6.857/2012/handouts At the end of the course students present research projects. They are almost always worth taking a look at because they tend to be highly creative and fun (the MBTA "T" hacking talk at Defcon was originally a project for this class): http://courses.csail.mit.edu/6.857/2010/pitches.html http://courses.csail.mit.edu/6.857/2010/pitches.html This class is excellent and Ron Rivest is very friendly and very approachable. If you have a chance I would recommend taking it (or watching it online). If you have a background in programming you can take this course.