Going on a date can be a nightmare for the best of us. But now a pair of 'social X-Ray' glasses promises to tell you exactly what the other person is thinking -- and when you should stop talking. The glasses have a built-in camera that monitors the other person's facial expressions and matches them up with 24 known features that convey emotions. It will then tell the individual via an earpiece and lights on the glasses what their date is thinking. In a traffic light-style system, a red light means negative, amber means they are moderately interested and green means your date is happy. The glasses are currently under development by researchers at the Massachusetts Institute of Technology's Media Lab. They say that wearing them during a conversation with another person is like having an 'extra sense' that they are bored or losing interest.