I really enjoy the adjective open. When applied to computer science topics is something that only offers advantages.
I'm not going to describe here the good things we have in open source solutions, and how incredible to visit sourceforge is in order to get almost everything you need but with an open license and with source code.
Recently, I'm enjoying with another application of the world open to lecturing. A fantastic example is the MIT. They have opened almost all the material they use in their courses, and believe me, they are worthwhile (go here). They have incredible lectures notes and even videos. I personally love the videos you can follow in subjects like Introduction to Algorithms. They are very useful and interesting.
Visit and enjoy the MIT OpenCourseWare and take the most of it !
