I feel participating in technical Forums aids as a supplemental learning tool as you get to know about other developers real-life scenarios. Understanding these experiences & their resolutions can be helpful in avoiding pitfalls & learning about best practices. For instance, did you know that the popular JavaScript Frame Buster code that prevents other sites from "framing" your site within an iframe can itself be busted.
In a relatively short time, Stack Overflow has become one of the most popular technical Forums (16 million hits a month, with currently over 0.5 million questions in all) on the Web. One of it's interesting features is that participants can vote questions and answers up or down and edit questions and answers in a wiki fashion. The best questions & answers cascade to the top based on votes. An active & open-minded community of users ensure frivolous questions and answers are voted out. You can also gain deep insight on some topics from gurus like Jon Skeet ("When you search for "guru" on Google it says "Did you mean Jon Skeet?"")
I've been following the top voted Q & A in some Web development topics via RSS & found them to be very educative. These can also be useful to those preparing for job interviews. To subscribe to a feed of your topic of interest, select a topic tag (like ASP.NET) and select the Votes tab to view questions sorted by maximum votes. Use the RSS feed icon at the bottom of the page to subscribe & view posts from your favorite reader.
Stack Overflow is a BizSpark startup which is built using the WISC (Windows, IIS, SQL Server, C#) stack and uses the ASP.NET MVC (Model-View-Controller) framework. It uses jQuery as it's client-side framework, OpenId for authentication, LINQ to SQL for it's Data Access Layer and Subversion for it's Source Control.