Outliner

This is a quick entry on some features of the Outliner--the view that displays the hierarchy of the objects in the scene.  The first concept is the visibility filter.  The combo box at the bottom which defaults to All Scenes, can be changed to any of the different filtering views.  

One that would be very helpful would be to set Visible Layers which helps make the Outliner more relevant if moving irrelevant (but needed) objects to other layers.

The next feature which is relatively new (probably 2.6) is the ability to drag and drop objects in the Outliner to achieve parenting.  The icons must be grabbed for this to work, not the name.  As well parenting can also be achieved with [CTRL+P] with the parent object being selected last.

Finally, it's worth mentioning the three icons on the right of every listed object.  These icons toggle visiblity in the scene (eye), selectability (arrow), and visibility in render (camera) respectively.