A very slim Pi Pico case. With a small hole cut out for cables. 

Hardware:  

• M2x10 bolt x4
  The bolts self-tap into the lower part.

I used this case to make a Key Remapper for a number pad. I do a lot of drafting at work on MicroStation,  this has all the shortcuts I use all the time. 
Here's a link to the GitHub I used for the project. 
https://github.com/jfedor2/hid-remapper
He also offers his own 3d case model, but I wanted to make my own.