Martha Stewart Living, July 2003
Cold drinks, slippery with condensation, can slide around on a plastic or metal tray, so line it with a sheet of cork to hold glasses steady. Rolls of cork sheeting, about 1/8 inch thick, are available at office-supply stores. Trace the bottom of a tray onto a piece of cork, and cut it out with scissors. Affix cork inside tray with double-sided tape.
I like this idea,, and cork has a nice look.