I'm somewhat startled that I managed to write this much about a darn mousemat. Yes, it really is free. No, they won't spam you.
Most computer users regard their mousemat, if they regard it at all, as a near-worthless item.
More savvy users regard it as a completely worthless item, because actually paying for a mousemat is a sign of foolishness, when so many companies are eager to give you one that advertises them. A friend of mine cherishes a mat which advertises, among other things, a manufacturer of small bore sewage macerators. For these people, the traditional rectangle of wetsuit-fabric or, more recently, rubber oblong topped with flexible plastic is good enough. The old cloth mats peel, and aren't very accurate, and collect crud like nobody's business. Which would be fine, if they didn't love spitting said crud onto your mouse ball.