Mr Chong Kwek Bin has spent years teaching people with disabilities to use technology and reshaping how Singapore treats its visually impaired – from pushing for 24-hour "locating signals" at pedestrian crossings to being a panellist at a United Nations conference. Every day, all around the world, pedestrians look out for the green man – the ubiquitous icon atop traffic poles that lets us know it is safe to cross the road. In Singapore, the figure's appearance is sometimes accompanied by loud,