Vesa Mount Headphone Holder
I originally printed a stand that clipped onto the side of my table but after dogs knocked it off I figured the unused VESA mounts on the back of my monitor would be a better storage solution that would be clean and out of the way.
You will need M4x16mm screws to mount this to your monitor
v.1.2: fixed holes, still off a little
v1.5: made mount high up to hold headphones off table