The guy sitting next to him can't believe what he just saw. He's more surprised when, 10 minutes later, the same guy walks back into the bar and sits down next to him.
The astonished onlooker asks, "How did you do that? I just saw you jump out the window, and we're hundreds of feet above the ground!"
The jumper responds by slurring, "Well, I don't get it either. I slam a shot of tequila, and when I jump out the window, the tequila makes me slow down right before I hit the ground. Watch." He takes a shot, goes to the window and jumps out.
The other guy runs to the window and watches as the guy falls to just above the sidewalk, slows down and lands softly on his feet. A few minutes later, the jumper walks back into the bar.
The other guy has to try it, too, so he orders a shot of tequila. He slams it and jumps out the window. As he reaches the bottom, he doesn't slow down at all. SPLAT!
The first guy orders another shot of tequila. The bartender shakes his head. "You're really an a**hole when you're drunk, Superman."