3-D has a strange effect on the bike, skateboard, and car stunts at the center of this doc about ESPN's yearly extreme sports fest. Set in the deep expanse of the screen, the athletes' hurtling bodies have the disconnected look of floating astronauts, and their motions become small, almost toylike. Obviously, the benefit of the gimmick is the pumped-up visceral impact of watching these men (and they are all men) go very, very high and very, very fast. Aside from unrevealing sit-downs with a few key players, X-Games 3D: The Movie is mostly an overlong demo reel of increasingly gutsy tricks, leading up to a set piece called The Mega Ramp: a Matterhorn-size slide that lets skateboarders shoot themselves 20 feet into the air. Of course, it really only takes one dimension to grasp how nuts that is.