In an effort to organize my workspace, I made these brackets to mount the cheap, small parts containers that many things from amazon come in. Also, these boxes are available for less than a dollar each if I need more.
I created this so that it's expandable by just printing another and mounting it in a line to get another column.
There are two sizes, currently because these are the boxes I have multiple of and they seem pretty common.
They are oversized about 1mm to allow some variance, and easy of insertion and removal and are angled slightly to hold them a bit more securely.