How to avoid accidentally relocating the 3d-cursor? Is there anyway to help avoid accidentally relocating the 3d-cursor?

You have all of these complex keystrokes in Blender like (CTR+ALT+SHIFT+C),
 but yet all it takes is a simple accidental left mouse button click to re-locate the cursor. 
How many hundreds of times I have done this and then had to move the 3d-cursor back where it was. Moving the 3d cursor is not stored in the Undo buffer, so you can't "undo" a relocation of the 3d cursor.
It is very frustrating.
I saw the same question with solution from a long time ago:
http://blenderartists.org/forum/archive/index.php/t-236492.html

I went to the user preferences and switched "Set 3d cursor" from "LMB" to "Shift + LMB".
Now I can no longer accidentally move it.