Check out this new service by Muchobene. It enables website and blog owners to add real-time chat answers from a community of people. Think of it as instant messaging meets Yahoo! Answers.
The first implementation is at Ubergizmo. Here the use case is that people can ask questions about gadgets of people who know about gadgets. Users who only want to ask questions can just ask away in the dialog area--that is, no profile, no registration. If no one is currently available to answer your question, you will received a "deferred answer" later.
Users who want to answer questions install a plug-in. Then the Muchobene engine monitors your discussions to determine your area of expertise. As an answerer you can tweak your settings for the quantity of questions that you receive as well as your availability.
I am an advisor to Muchobene.