activity stream with asp.net

          I have a ASP.NET website with multiple pages. In some of the pages the user can perform certain actions (post a question, rate an answer, etc). When any of these actions occur I would like to have an activity stream updated (and a message like "user x posted a question" or "user x rated an answer"). I don't have the form of the activity stream defined at this point. It may be a classic ASP.NET control, ajax toolkit control, etc. I just want that section of the page (the activity stream) to reflect the user actions chosen for monitoring (posting a question, rating an answer, etc.) Any ideas?
 
Any help is appreciated:)
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