Check out http://37signals.com/svn/posts/3122-the-new-basecamp-interface-details-and-power-user-goodness http://37signals.com/svn/posts/3122-the-new-basecamp-in

Check out http://37signals.com/svn/posts/3122-the-new-basecamp-interface-details-and-power-user-goodness http://37signals.com/svn/posts/3122-the-new-basecamp-interfa..., there's a great video that explains some of the goodies baked in for navigation.