Hook to hang a towel to a kitchen furniture knob.
This one is printed with FormFutura Centaur PP which allowed the realisation of a small flexible tab so that each parts remains atached when not in use.
Contrarily to its reputation, I didn't find PP extremely difficult to print and I think it is a really awesome material.
There is however a version for rigid materials: https://www.thingiverse.com/thing:3340792
FormFutura Centaur PP Polypropylene PP
PP packing tape on glue stick on glass. (Glue stick so that the adhesive residues left by the packing tape are easy to remove)