I saw a Prusa post a few months ago about some new infill options they added to their Slicer and decided to print some samples so I can reference them when deciding what to use for a print. I copied their hexagonal sample idea, and after a bunch of these hexagonal pucks sat on my desk for a while I decided to mount them on the wall.

https://help.prusa3d.com/en/article/inifill-patterns_177130

Excluding the set my daughter made me print for her, the samples I made were all from one silky gold metallic filament which shows the bed texture and layer directions up well. Samples include ones focused on infill, combinations of first layer texture of steel sheets on the bed (at the time, just smooth and textured, I now have satin sheet samples to print), and bottom fill pattern.

Of course, with infill, different percentages mean there are thousands of combinations. You could also just simply print samples using different filaments, leaving the infill or bottom fill pattern static.

The hex blank sample puck is printed using various infills etc, and no top layers - as many as you need. The black holder is printed in three sections, a Left, Middle and Right, each holds 9 samples (Left holds 10) and snap together.

Holder options are varied:

To display just 10 samples, print the Standalone holder.
To display 10 samples with the option of extending it, print the Left holder.
To display 19 samples, print Left and Right holders.
To display 28 samples (as pictured), print Left, Right and Middle holders.
To display more than 28, print more Middle holders, each adds 9 samples.

It's modular, lightweight, prints fast, and just hangs on a couple of pins located behind the 'first-layer' samples which are hollow on the back side.

It is a little flimsy, depending on your filament, and may work better with a spot of glue, but I've included the OpenSCAD file if you want to modify the depth of the holder etc.