Ahh, sorry, it's a bit of a ROGeR (Really Obscure Geek Reference): it's a glider from John Horton Conway's Game of Life. If you follow the link, read the basic rules, and then scroll down to examples of patterns, you can see the glider in action in a nifty little animation. (Be warned: once you start doing the Life thing, it is extraordinarily addictive. Approach with caution, Grasshopper.)