After 9/11, there was all sorts of talk about how there would be a boom in the markets for security and surveillance technology, with facial recognition technology seen as a key area. That sounded great... except for the simple fact that the technology doesn't work. Various tests of the technology for security purposes found that it not only didn't catch any criminals, but it couldn't even catch the control "tester" criminals. Basically, the technology isn't good at seeing someone walk by and identifying exactly who it is -- which is necessary for such security purposes. However, if you dial back the requirements, the technology is probably at least decent for recognizing if someone is male or female, young or old. That's why we see it being used for age verification in Japan, and now it's starting to get used for customized billboards around the world. The billboards include small hidden cameras that try to determine general demographic, and then the billboard will play a video add targeted to you. It's not quite Minority Report where the ads are perfectly targeted -- but unlike in using the technology to search for terrorists, these billboards don't need to be quite as exact. And, of course, the other benefit to all of this is that the billboard companies (in theory) get a better idea of who's actually looking at the billboard -- something that companies have struggled with for years.