This is a great execution from Amnesty International in Hamburg, Germany, calling attention to the problem of domestic abuse. The billboard features a picture of a happy couple standing together with the caption, “It happens when nobody is watching”. When the observer looks away the image changes to the man abusing his partner.

The billboard works by scanning its proximity with an eye-tracking camera, which triggers an image switch on the display panel when it senses someone looking at it. The change only occurs after a brief delay, so that observers understand what’s going on, and get the message.

This received a lot of press and consumer interaction and is a fantastic way of calling attention to and illustrating a difficult concept.

What other propositions could be applied using this technology?

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