Not being much of a extreme sportsperson myself, I wouldn't mind trying Zorbing, otherwise known as Sphereing - the popular sport that originated in 1994 in NZ (the image is from the Rotorua site), where you climb into a giant plastic transparent sphere and roll around, not unlike a hamster in a hamster ball.
Here's a link to footage of behind the scenes at the shooting of the 3 TVC: http://www.youtube.com/watch?v=iDz7wDGphuI&feature=related
It's pretty sweet actually seeing the zorb ball roll onto a car! It reminds me of the Sony Bravia LCD ad featuring the rubber balls bouncing down a San Francisco street along to one of my favourite songs: Heartbeats by José González.
And another link for Neopolitan Dreams live on Lisa's YouTube channel, which I actually prefer than the released version which has the overlap: http://www.youtube.com/watch?v=hZ3Wn50Df0U