For a variety of general information, that is both informative and entertaining you should ceck out Ed Skoudis' page.

http://www.counterhack.net/

He periodically issues hacker challenges done in a parody format (Matrix, rudolph, Lord of the Rings Etc..) and ties it to a vulnerability, or class of vulnerabilities. They are all still available on his site, as well as the wining answers he recieved for the challenges. You could read the challenge, do your best then go back and check the answers on the site. Just a suggestion.

By the way Ed is the primary instructor for SANS Track IV, Hacker techniques and methodology.

And I agree Happyhacker is next to useless.