A few years back my dentist insisted that I start wearing a "Nightguard". The storage box that came with it is fine, but I wanted a couple more for Travel, Backup, etc.

This is my design.

When I print it though, I set the parameters to print with "NO BOTTOM". That way whatever "Infill Pattern" I am using gives the box some character when it is removed from the bed.

This also helps with bed removal, less filament in contact with the print bed.