What setting locks local rotation and scaling of an object? I have encountered a strange phenomenon, it must be some key I hit but I have no idea what!

All of a sudden I noticed that nothing will rotate or scale in object mode in a project I am working on.  After playing around with some basic settings I noticed that when I set the pivot center to the 3d cursor and try to rotate something it simply moves the object around the 3d cursor without rotating it.  Scaling the object moves it towards or away from the 3d cursor.  Here is a picture:



It seems that I have somehow locked local rotation and scaling of all objects, the only way I can rotate or scale anything is in edit mode.  How on earth did I do that and how do I turn it off?
It sounds like you have activated the Manipulate Pivot Points tool.  It's found directly to the right of the Pivot Point selection menu in 3D view > Header.

Here's a demo.



It can also be toggled with &#9095; Alt, (comma).

Now, if you mistakenly press some keyboard shortcut that ends up causing you grief like this; you can try pulling down the top header bar to view the Info area.  It should contain most of what you've recently done.(to view EVERYTHING you'd have to enable debug logging, that's gets messy quickly)