The business card holder of the DOMOBITS family combines a standard horizontal card holder with a vertical card storage slot, for a very unique presentation. The bottom surface is detailed with a series of concentric ridges, with a wide outer ring to provide extra grip for attaching a self-adhesive felt or rubber pad, if desired.
For a rubber pad, I recommend adhesive-backed neoprene rubber from http://www.mcmaster.com; their Item 1376N33, is a 4” wide x 36” long x 1/16” thick strip in 60A ( Medium Hard) durometer. The cost is under $20, and one strip yields a dozen pads for any DOMOBIT.