So you are like many who have one or more hard drives attached to your MacBook via Firewire or USB? And, like most folks in that situation you inevitably forget to eject those hard drives before you leave and thus you see the annoying error message after closing your MacBook and yanking out all the cables the next time you open it up. In walks “unDock”. A very handy and inexpensive tool available at the App store:
The Intentional Geek 