Someone has invented a new privacy product,
a flash-photograph-resistant scarf: The ISHU scarf is made of a special fabric (enhanced with thousands of nano-spherical crystals) that reflects light back into a camera, basically rendering all flash photography useless.
The idea is that you wear it near your face, and when a flash goes off, it reflects so blindingly bright, your face is lost in the shadows.
Also available as a necktie and pocket square, and soon to be available as a phone case.
h/t
Buzzfeed, demonstration pictures at that link.
It's mostly an anti-paparazzi device, not an anti-surveilance device, because it only thwarts "good" photos, not adequate-to-identify-someone photos. But as a scarf-wearing privacy freak, I still kind of want one.