I combined Geekdad's AirPort Express mount with a shelf adapter I made early on in my 3D printing life.
I had created a cable channel adapter to mount to the back of my stereo stand without any permanent fixtures, it uses sticky felt pads that I cut to size to grip firmly but not damage the wood (finished walnut). I bonded the two together in TinkerCAD, added a little reinforcement and some vent holes since it has top and bottom coverage now. I used Matter3D PLA+ in matte grey to print. Makes a pretty strong enclosure that holds the unit in place even with cords coming out the back.
The author remixed this model.