Check out this video of a French Gymnast/Lunatic/Spiderman, David Belle, as he runs around grubby urban landscapes jumping off roofs and between buildings. Forget all the freestyle-extreme-jackass stuff.... this guy will jump off a 30' building and do a complicated diver flip/spin/sault to land on a concrete deck.
They call this new sport 'Le Parkour'. The best videos show David Belle, definitely the seminal monster of the community, while the other videos have more "normal" guys, mostly jumping over railings and other quaint things.
BBC ran a decent article summarizing the sport.
This definitely blows away my old favorite video