The lying down game (also known as planking, or face downs) is an activity, popular in various parts of the world, consisting of lying face down in an unusual or incongruous location. The hands must touch the sides of the body, and having a photograph of the participant taken and posted on the Internet is an integral part of the game. Players compete to find the most unusual and original location in which to play. The location should also be as public as possible, and as many people as possible should be involved.
So, apparently this started in 2007. We're just a few years behind, and have only practiced so far in not-so-public places...but I think we're getting the hang of it: