People like Aron Ralston

Aron Lee Ralston (born October 27, 1975) is an American outdoorsman, mechanical engineer and motivational speaker known for surviving a canyoneering accident by cutting off his own arm. During a solo descent of Bluejohn Canyon in southeastern Utah he dislodged a boulder, pinning his right wrist to the side of the canyon wall. After five days he was able to amputate his arm with a dull pocketknife, make his way through the rest of the canyon, rappel down a 65-foot (20 m) drop, and hike 7 miles (11 km) to safety.

The incident is documented in Ralston's autobiography Between a Rock and a Hard Place and is the subject of the 2010 film 127 Hours where he is portrayed by James Franco.