Rotatating in view and local

This might seem insiginficant but it seemed to me a major detail.
 When working the animation there were many times I wanted to rotate the an object around its center. That is fine when in upright position when its aligned to the world, but what happens when you have rotated the object already?

The amazingly simple solution is to select the object, select the rotate tool and then set it to "local" on the pull down menu next to it. Dead simple but I did not know it existed and did not know how it worked.

I think it would a great addition on your lecture notes to emphasise the use and the existence of the pull down menu for moving and rotating in "view" and "local" mode.