Back of the Door Cabinet

"This ingenious slim storage cabinet takes advantage of the unused space behind a door by attaching to a door's existing hinges. Once attached, it swings open to reveal up to six adjustable shelves with retention rods to keep objects from falling out. Makes a great spice rack in kitchen pantries, nice for organizing toiletries in the bathroom, or myriad other possibilities — as long as there's at least 3.5" of space between an adjacent wall and the door's hinge pins."  

$129.95.

[via The Green Head]