A guy walks into a bar right at the top of the Grand Canyon. Another patron comes up to him and says "did you know the air currents in the canyon are so strong you can jump off and they pull you right back up?" "What?!" the man said "you must be drunk." "No really, watch this!" and he jumps into the Grand Canyon, and WHOOSH! flies back up. "That was amazing!" the second man said so the first guy does it again. Finally the second guy decides it really does work and goes for it. He jumps off and splatters on the ground. The first guy returns to the bar and the bartender says "Damn, Superman, you sure are a jerk when you're drunk."