Head-mounted displays are frequently supposed to keep your hands free, but they only sometimes live up to that promise. You can't really dictate a message in a noisy warehouse, can you? If Fujitsu gets its way, you won't have to. It just built a smart ring that not only allows for motion control (something we've seen before), but in-air handwriting. All you do is trace letters with your fingertip, and the motion sensor translates those scribbles into usable characters -- supremely helpful if you need to send a quick reply when you don't have access to a keyboard. There's an NFC tag reader in the ring, too, so you can get instructions for working on a device just by tapping it.