Just a fairly simple coaster holder I designed for using these coasters (https://www.thingiverse.com/thing:1155831). Holder will stand up for display, or with the addition of more rubber feet on the back you can lay it flat.

The cap was scaled up from this design (https://www.thingiverse.com/thing:2059192) and modified so the pieces inside the lettering would fit better (some sanding is most likely going to be required anyways). I also have the lettering protruding a few mm to give make it stand out a bit more.

Print, sand, glue, add rubber self-adhesive feet, done. Enjoy :)