This is an interesting application of probably a known concept. Spectacles specifically privacy spectacles of different styles could become a big part of new fashion very quickly.
Adding a filter to secure your screen is hardly unusual, but a new monitor hack actually works better by removing the built-in polarizing filter. An LCD with no polarized film simply displays white light, but popping lenses made from the film into a pair of glasses lets the wearer use the computer normally. And you thought 3D glasses looked silly. Read the full instructions for making a privacy monitor at the source below.