Mike Phillips pointed me in the direction of this project. Built by Sascha Pohflepp, the Buttons project lets you take empty photos that record only the time of your snapshot. When you take your blind photo, the device searches the Internet (via a custom Mobile Processing app) for other peoples' pictures taken at the same time. After a while, those images will appear on the screen.
The concept is nice, and certainly looks slick. With distant memories of Toupix, this type of work is of great interest to me, and with other projects like Radar, it's good to see how this field of research is developing.