Like the iPod Video Privacy Filter, this laptop filter’s sole purpose is to keep lookey-loos away from your confidential data. Tailored for 12 to 19 inch screens, your coworkers sitting to the left or right of you will only see a black as dark as the soul of your mother-in-law—all while keeping your view as clear as day, albeit a slightly darker day than before.
https://gizmodo.com/ipod-video-privacy-filter-155921
They even come with some self-adhesives to keep the screen in place when closing and opening your notebook.
3M Laptop Privacy anti-peek filter [Reg Hardware]
