The side bar is something Lotus Expeditor adds to the Eclipse framework. In Notes 8.5 you can do some pretty neat things with the side bar. Here is what you can do from several different perspectives:
The Side shelf API's allow you to contribute and manage the side bar. You can open views, add views, close views, etc within the side bar from Java.
Using those same cool API's, the Composite Application area allows side shelf components to be placed on the LEFT or RIGHT side bar and also be wired to and from those components. The composite application editor allows you to define when the side bar view is shown – currently two options:
1) when the composite application is open or
2) when the composite application has focus.
So now, an assembler can easily manage what shows in the side bar with respect to their composite.
The bitmap below says it all! Dragging the sash to the top or the bottom makes all of the side bar components icons so the side bar is no longer cluttered. You also have some new options on the view menus to send them to the icon bar. Very cool.