coolRunnings is the service that powers SpriteMe.
Description from old hg repo:
"a css sprite generator written in php. See, it's like when you put the sprites into one image, it's kind of like packing a bunch of guys into a bobsled. And then the guys all go really, really fast in the bobsled, all together at once. Which is kind of like what a CSS sprite is supposed to do. Cool Runnings being, of course, everybody's favorite bobsledding movie, it seemed a natural choice..."
Learn more: http://jaredhirsch.com/coolrunnings/about