This gadget is used by employees at Google and Facebook to increase their productivity. It's called a busy flag and to set it up you just plug it into your laptop and attach it to the back of your screen magnetically. Then when it glows red it lets your co-workers, husband, wife, kids, granny or pet dog know that you're busy and not to disturb you. However, When you’ve had enough of work just change it to green to show that you’re happy to be interrupted!