Parkour, the extreme sport that including running, climbing, jumping, and other insane movements in an urban environment, is pretty popular - and ridiculously dangerous.
Normally, parkour devotees attempt to scale walls using nothing but their feet, jump long distances between buildings, or vault themselves over unmoving objects like park benches or railings. It's perilous, but it's nowhere near as much as what these guys are doing. You're going to be on the edge of your seat for the entire 83 seconds of this video. - that last stunt almost made me cry.
Have you ever seen Damien Walters? He's like a human rubber ball.