Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:6248213.

Clamp this to the edge of a desk, or put something heavy on it. Then you can put a folded cable into the slot. Both of the ends stick up so you can see what the cable will connect to. The folded sides don't tangle much, and even if they do overlap they are very easy to separate.

The circle on each side holds a carabiner so you can attach your keys or other gear.