I use keyboard shortcuts probably 95% of the time, so having the toolbox open is a waste of space, especially when the toolbox insists on staying on top of the image window. There doesn't seem to be any way of hiding the toolbox and the best I can do is to drag the majority of the toolbox past the borders of my display. 

There is also no way of minimizing the toolbox, which is another pain. When I minimize GIMP to try and get to something on my Desktop, the toolbox stays open, so if I want to get something that's behind the toolbox, I have to drag it over. This behavior seems to be inconsistent with most applications; if an application is minimized, then all components of the application should minimize or be hidden until the application is restored.

Proposed enhancement:
Allow toolbox to be hidden or displayed from View menu.

Possible bug:
Toolbox should be minimized or hidden when GIMP is minimized.