I cannot believe I did not jump into these communities earlier - StackOverflow and ServerFault are two amazing community websites in question-answer forum fashion about programming and software development, and IT administration, respectively. I have occasionally landed on StackOverflow doing Google searches for programming-related problems, but from now on, I will be starting there and moving outward as needed. A nice feature about both sites (which use the same custom framework) is the "interesting tags" feature, which allows you to fine-tune your preferences and tailor the homepage to your interests. Both sites integrate with each other and use OpenID for authentication.
Have a look!
Registered Linux User #370740 (http://counter.li.org)