After I'd bought several Cricut cartridges, I started realizing that keeping them in their original boxes was getting awkward. There had to be a better way to store them. After looking online to see what other Cricut owners use, I decided to try Snapware and went off to JoAnn Fabrics to find the Snapware Ribbon Organizer that most Cricut owners seemed to use. There were NO Snapware ribbon organizers to be found. However, JoAnn's did have other Snapware containers that looked like they'd work with a little adaptation.
The left side (front) shows how I cut plastic canvas to make dividers that interlock, as well as how the dividers fit together in the container (back). I cut three long dividers, and four short ones. This gives me room to store up to 15 cartridges, with room enough in the same container for the overlays. I keep the handbooks in a separate container. Notice how the handbooks are kind of staggered in the container. Snapware containers snap/lock together, so I can snap the cartridge/overlay container on top of the matching handbook container, and keep them together; or I can snap multiple cartridge containers in one stack and handbook containers in another stack. I tend to do the two stacks. They have a handle on the lid of each stack, so they're easy to carry if needed. It works well for me, and it's pretty quick and easy to find the cartridge I want, since I store them in alphabetical order. I used a fine point Sharpie to write the name of each cartridge on the top so I can see the names without pulling them all out.