Steve Caplin tells Simon Rose about the latest tech developments. There's a demo of AI computer game characters who can interact realistically with players, devices to help deaf concertgoers and blind subway users, how simply thinking about music can now actually produce it, glue that can be unstuck on demand, a camera so fast it can capture light in motion and take photos in almost total darkness, an electric guitar for children, why bras may be soon be able to check for breast cancer and how buildings made of concrete could become giant batteries.