Rolling down a hill in a giant inflatable ball

That ball had better be inflated, not just inflatable. "Zorb is the sport of rolling down a hill inside a giant inflatable ball and where New Zealand, once again leads the world in stupid things to do while you're on a vacation." Now available in the USA near Dollywood, Pigeon Forge, TN. Mentioned because of the question that arose while watching the current Toyota Sequoia commercial, "What in the world are those people doing?"

Much more, of course, at Wikipedia. Here's a video from National Geographic.