What if you had a disc whose surface never touched a tabletop? Todd Kuchman, founder and chief executive of Scratch-Less Disc Industries, came up with a low-tech fix. He added a series of bumps around the edge of the disc, keeping the surface slightly raised.
The Scratch-Less discs are available at a few stores, like Micro Center and J&R, and online at places like Amazon.com for about $1 each, making them slightly more expensive than other discs. But in one unscientific test, a Scratch-Less disc still worked after a 175-pound man ground it into a rug and then rubbed it across the top of a metal file cabinet.