Two men sitting at a window table watch as the man plummets to certain death. But, as he is about to hit the ground, he rights himself, pulls his feet underneath himself, and lands softly. He turns and comes back into the building. Naturally, the two men are stunned. The guy comes back into the bar, orders a few drinks, and does it again.
The men at the window seat are flabbergasted! When the guy returns, the two men stop him before he jumps again and ask him how he does that.
"It's simple, really. There's an air vent down by the ground, when you catch the updraft, you can right yourself and land on the ground." He jumps out the window again.
The two men, of course, decide they have to do it too. They jump out the window, and SPLAT!
The first guy ambles back into to the bar. He sits down to order a drink, and the bartender says "Superman. . .you can be a real a**hole when you're drunk."