Whhooohooo, 100 posts since september of 2006!!!
This is essentially a list of every single keyboard shortcut available in OS X. To access this list, open System Preferences and proceed to the Keyboard & Mouse section. Then click on the Keyboard Shortcut tab. This brings up a menu of every keyboard shortcut that’s built into OS X.
To enable pre-existing shortcuts, put a check mark next to the Description, to disable a shortcut, uncheck it. You can also add your own, as well as remove defaults by pressing the + or - buttons respectively. To restore the shortcuts to factory settings, hit Restore Defaults.
I also have a list of other important and obscure Mac keyboard shortcuts.