Since the golden age of television, we've been watching firemen and police officers put their lives on the line in order to protect the innocent. But those are just actors and although a few have been known to get hurt in the performance of their duties, acting isn't usually a dangerous profession. On the other hand, the stars of these four reality shows are truly risking life and limb every time the cameras roll. Why do they do it? Because with big risks, come big rewards.