These are some links to resources that I find valuable broken by category.
Pen-testing and Security
http://www.offensive-security.com/
http://www.backtrack-linux.org/
http://www.social-engineer.org/
http://www.attackresearch.com/
http://www.overthewire.org/wargames/
Programming
If you’re looking for some good starter classes to learn programming, or simply need a refresher, I recommend Google’s introduction classes to Python and C++: http://code.google.com/edu/languages/index.html
That’s a start…I’ll try to add more links as time goes by, but remember that Google is always helpful.