Quickly rearrange your dock!
Okay, so this is really an extension of the tip about the keyboard shortcut for the Dock (Ctrl-F3 or Fn-Ctrl-F3). I started using it a lot and I discovered that you can also use this shortcut to move applications around on the Dock. Once you used the same key combination, you can move the icons around with "Alt-left or right arrow" (or Option instead of Alt if you prefer, same thing really!).