For more than a decade, Silicon Valley has been trying to convince us that the next big thing would be something you wear. The pitch was always slick: computers so seamlessly integrated into our lives that we’d barely notice them, devices that would augment reality and make us all cyborgs. The reality has been a parade of expensive — or worse, deeply uncool — disappointments. Advertisement Google ( GOOGL ) Glass promised to put the internet directly in our field of vision, only to become a