A hook that you can clip onto then end of a horizontal surface, such as a tabletop, bookshelf, etc. to hang things on.
I'm using it for hanging a basket with filament on. I'm using Vik's Y-bearing holder to make sure that it can rotate (see http://www.thingiverse.com/thing:921 ). I put a loop of rope through the two holes that hang over this tabletop clip.
Version 2.3 has some improvements, the hook's lowest point is now nearest to the table. A cord will tend to rest there causing minimum torque on the hook-clip.
It is made stronger at the two 90 angles that have to withstand forces. This is a more efficient use of material and builds faster.
A hole under the hook where no material is required for an adequate strength of the hook.
Version 2.3_thin is simply for a thinner tabletop/shelf.

1. Scale the height to fit the height of your tabletop or shelve. It should be slightly too small so that the tension of the 'springy' mechanism will clamp the tabletop.
2. Scale the Z-axis of the model up if you need a more rigid structure. The current version is designed to carry 5 kg of filament easily, being only 5 mm thick. This was tested in ABS as in the pictures.
3. Skeinforge it, print it!
4. And you're hooked!