Around our house, we like to rearrange things quite often, so we ended up with some modular wire shelves to store things in (C&A Home cube storage). However, we noticed that we did not have enough clips to arrange everything exactly how we wanted, so I took to fusion360 and designed these. 

They are not perfect, but I uploaded the best iteration I have so far, which has stronger walls. I printed in PLA with supports touching the build plate only and they were easy enough to remove. I printed this on my ender 3 v3 se and prusa mk3s and both worked fine, although with the orientation I printed them at the bottoms are prone to detaching themselves from the rest of the clip. Other orientations may require more supports but I suspect they may also be stronger and better suited for real world use. 

If you want to try with PETG, ASA, ABS, or any other engineering filament please let me know how that goes in the comments (if you have any suggestions for improvements pls let me know and I can either find time to make those or upload the f3d file for people to adjust as desired :))