My ball python has crawled, and in turn fallen, off my bed a couple times (on to carpet), and one time decided he was tired of holding onto my arm, went slack, and dropped onto the kitchen floor. A lot of snakes like to climb, and the great thing about animals that can climb, is they can also fall. And like xFenrir said, they have large amounts of muscle, so the odds off any amount of damage being done is very slim.