The Modular Prusa CORE One Side Storage (https://www.printables.com/model/1341465-modular-prusa-core-one-side-storage) system is great.

I have designed some quick additional modules to suite my tool storage needs.

I added some inserts for the author's original 4x nozzle module. I only have 1 spare nozzle, so can use the 3 unused slots to hold the screwdrivers from my Core One kit and some tweezers.

I also added a variation on the “Brush and Clippers” module to only hold my flush cutters, which are slightly larger.