We were playing with Microsoft’s newly released Face detection API’s through a webpage called http://how-old.net. This page lets users upload a picture and have the API predict the age and gender of any faces recognized in that picture. We sent email to a group of several hundred people asking them to try the page for a few minutes and give us feedback – optimistically hoping that at least 50 people would give it a shot. We monitored our real time analytics dashboard to track usage and, within a few minutes, the number of people using the site vastly exceeded the number of people we had sent our email to. We watched the usage quickly spread across continents, and, 3 hours later, we had 210,000 faces from all over the world.