Virtual Magic talks about the French discipline of parkour:

Parkour is a physical discipline inspired by human movement, focusing on uninterrupted, efficient forward motion over, under, around and through obstacles (both man-made and natural) in one’s environment. Such movement may come in the form of running, jumping, climbing and other more complex techniques. The goal of parkour is to adapt one’s movement to any given obstacle.

Could be a fascinating sport to get into. Urban obstacle course running…