I installed yesterday an amazing looking Java-WebStart application: http://www.shwup.com/. I cannot tell you what it does, but it looks great, the user-interaction is also interesting.
It takes a while until it is installed - but it could be probably solved. Just forget Web 2.0 with all fancy acronyms - we have already Web 3D :-).
NEW: Online Workhop Effective WebApps without Frameworks is also coming to: MUC Airport.