I've built quite a few of these lately, so I wanted to share it with others and say something about each one.
I hope you'll find some of these useful. :)
1. Keyholder:
This one I built quite a while ago. It's pretty durable and you can spin the keys around.
https://rebrickable.com/mocs/MOC-171645/N1K0L4/lego-keyholder/
2. Camera stick with stabilization
I built this at first to help me shoot my RC creations while driving them, but I can use it as