Please help me design my application

I see a situation where several people are online at the same time in a discussion. One of the people would be the chairperson.<br><br>I would like the following features:<br><br>* A 50-50 forum-chat. The forum-chat would need to allow for 3-4 simultaneous threads to be open (perhaps with a tab allowing the user to switch between them). Everytime someone posts to the forum all participants would immediately see the new post. I want these posts to be threaded.<br><br>* It is necessary to allow participants to discuss with a) each other, b) everyone, c) only the chairperson - so I need 3 separate dialogs, and these dialogs would be available after the discussion for reference. I want to allow some of these threads to remain private (secret discussions made between a limited number of participants during the conference.<br><br>* The chairperson will be able to control the discussion by sending content to the participlants such as html, graphics and sound. Only the chairperson will have these rights.<br><br>* The participants in an online chat/forum could discuss that content - which the chairperson would be able to upload (the other graphics and text) during the discussion. (or perhaps draw upon previously uploaded content).<br><br>* I would also like a feature that allowed users to draw simple diagrams while the discussion was going on. (especially the chairperson).<br><br>* I'd like this to be implented in a browser - perhaps with plugins.<br><br>Is want I want easy to do with ASP.NET?<br><br>I would like to write this as a general purpose application configurable for each particular group - although I do have a specific application of my own in mind.<br><br>Has someone already written an application like this, with the code freely available? I would prefer not to have to write this as it must be many months hard work.