In Japan, snowball fighting isn't just a pleasant winter pastime. It's a serious competitive sport known as Yukigassen or "snow battle." Two teams square off on a field about the size of a hockey rink. Victory comes through annihilating the other team or capturing its flag. See more photos and a video at the link. This particular photo, I should note, is from a match in Alaska, not Japan.
Link | Photo: Roy Neese, Anchorage Convention and Visitors Bureau