The Envato Wiki is a fantastic place to get the questions you have answered about any of the web sites available in the Envato network. The site is a custom Wordpress theme with a plugin created specifically for it that displays Frequently Asked Question.

This theme is another unusual and creative way to use WordPress, as a wiki or knowledge base web application. You can also purchase a similar theme I created that was modeled after this one over at ThemeForest.net.