I needed an easy way to display my boxed Funko Pop figures, so I designed a shelf that only requires two pushpins to hang on a wall. Aside from the two pieces adding support underneath, and the lip, the shelf is practically invisible when printed in white.
The shelf is mostly a frame to conserve filament and also has a lip on the end to stop the box from slipping off if the shelf tips forward.
Print upright with the shelf facing upward. Use white filament to have it barely visible.