With base jumpers around the world competing to stay at the cutting edge of the sport, they're having to become more and more imaginative about where they leap from.
These two chaps decided do it of a moving cable car - while being called "freaks" by the startled passengers.
Austrian Pro Freerider Flo Orley and French/American Pro Freeskier Matthias Giraud opened the emergency exit on the roof, climbed out and locked the hatch.
Then they jumped performing a tricky landing in a narrow gorge.
They would like to stress the pair did not damage anything during the project, nor did they put any of the other passengers in any danger.