Kryptex

Prusa Mk3S+ PETG 0.2 quality 15% infill
no support (except key bit at enclosure and inner tube)
Endcap/inner Tube, Cap inner/Tube outer, Pullring/Tube outer needs final bonding - not necessary for testing.

When the cryptex is open, the code can be freely set by pulling (carefully and evenly all around!) on the pull ring. The new code is adopted by pushing the pull ring back.

There are already a lot of things out there.
The core idea was a convenient way to change the code, similar to luggage locks. I didn't find anything like that anywhere.
I also wanted it to be a bit bigger. 
The focus was more on technology than on style.
You can still make it pretty.
I like it but rather simple and functional.

Have Fun!

Edit: An error has crept into the exploded view - the order of the inner digit ring and digit ring has been reversed.
Please note this!
I will correct the view as soon as possible.
Sorry for any inconvenience...