When Facebook reached 500 Million people using the site we wanted to do something to announce it. What better way than saying thank you to the very people who make Facebook what it is. Without each and every one of them we wouldn't have the inspiration and motivation to continue to build and innovate.
Facebook employees coordinated a massive effort to create signs and submit images of themselves to thank everyone who uses Facebook. We then used Cooliris to create an online visualization of all of the images.
Here is a small sampling of some of the images. The creativity and diversity of submissions was amazing.