Project Orion's 10-12m variants used an external pulse unit storage that was a helical magazine. This coaster is in the shape of the loader floors that sourced pulse units from 6 magazines. But without a top, which provides textured surface with deep liquid drainage in the case of spills or condensation.
Pulse unit and magazine design is based on both GA-5009vIII, a declassified document detailing project Orion, and Aerospace Projects Review Volume 1, Number 5 by Scott Lowther, in particular the diagrams on page 46.
Heavily inspired by Winchell Chung's Atomic Rockets and his Orion mod for KSP, see http://www.projectrho.com/public_html/rocket/
This shape is the best example I have come across (outside of biology) of functional systems producing a shape that's beautiful to the eye. When I started this 3D shape, I knew I liked the design, But not until I replicated all the parts and saw it as a single piece could I appreciate it fully. I'm in love with this thing. So, I'm ordering some, even though it's a weeee bit expensive for a drink coaster.
NOTE: The frosted Ultra Detail and HD Acrylite options are just included for completeness. They don't have very good temperature resistance and shouldn't be used for hot beverage coasters (probably fine for beer coasters etc).