*Smile Or The Billboard Next To You Will Advertise Anti-Wrinkle-Cream To You: Camera In Billboard Analyses Your Face As You Walk By

Two years ago a Japanese company started to attach a little camera onto its billboards to be able to measure who much attention they attracted, or to be more precise, to measure how many people looked at their billboards. There is also a second camera below the billboard which counts the total number of people who are near the billboard, allowing to tell how many of the people passing by actively looked at the billboard (eg 50 out of 200 people walking by).