It is very important to avoid touching your eyes, mouth, and nose to prevent the spread of infectious disease. However, this tends to be very difficult to remember through the course of the day. In fact, trying to avoid touching our faces often serves only to remind us just how frequently we do touch them.
Sentinel was designed to provide a subtle reminder not to touch your face. When your hand approaches your face too closely, a red light will appear in the your peripheral vision in time to modify behavior.
https://github.com/nickbild/sentinel
https://www.youtube.com/watch?v=yMnGv9zEGWM