This is another purpose built hook. In the cube I have at work we have these shelves which I wanted to hang something from. On close examination I noticed there was a metal lip which might be something I can work with.

These hooks are designed to clip onto that metal lip and then provide a general purpose hook which can hold wires, headphones, or other things you'd like to get off of your desks surface.

I've uploaded my original sketchup file as well as the STL for this, enabling folks to customize if they would like to.