The National Retail Federation reports that Visa has introduced a "payment ring." It's the first of its kind, and is backed by a Visa account and will be given to all 45 Team Visa Olympic athletes in Rio. The ring uses a built-in NFC-enabled antenna that enables contactless payment capabilities. Unlike many other payment wearables, the ring does not require use of a battery or recharging. Obviously rings have a pretty meaningful significance to Olympic athletes, but what about the rest of us? Can you see this working here?