Scalable Box with Connectors

You need FreeCAD to create boxes. Add the python file to your .FreeCAD/Macro directory and then add a toolbar with the macro like here:
https://wiki.freecadweb.org/Customize_Toolbars
Then you can create Boxes, export them as stl and print them.
Almost all sizes are customable in the freecad object menu.

I created boxes to organize compact discs (CD). But you can use them for anything. Books, screws, Lego, ....

Adjustable Parameters:
* Size of box
* Wall thickness
* Edge rounding
* Connector sizes of horizontal and vertical connectors
* Gap between male and female connector
* Connector location and appearance
* Lattice on/off for every wall
* Lattice size

Printable without support.