I think it is excellent that you are attacking the context bar problem Lars! I have been frustrated myself that the ACS doesn't provide an elegant solution to the problem, but as your post indicates, the problem is much harder than it may seem at first. When I wrote the categorization service in Munich I implemented a little navigation package that used a URL-based session id to keep track of the urls and context bar names of the pages the user had visited. That way the user could click on the "Administer Categories" link in a Bboard forum and be taken to the categories package without the bboard pages disappearing from the context bar. I guess being able to clone the browser window and browse in different directions is useful sometimes. I am not convinced a lot of users take advantage of this feature though.
