A bar on the 15th floor of a complex is hoppin' with tons of people one night. Someone orders this crazy drink that's bubbling and fizzing like a science experiment gone wild. He drinks it, wanders over to the window and jumps out.
Everyone looks in horror as he plummets to certain death, but instead he bounces off the pavement right back into the window. He saw all the confused and shocked looks, and people started betting he couldn't repeat it. Again, he leaps out the window, bounces, lands back inside.
A second guy, already kind of inebriated, asked for the same drink the first guy had. Yeah, he was sure, so the bartender mixes up the same bubbly fizzy drink. The guy gulps it down, dashes towards the window, hops out, and ends up as a mess on the pavement.
The bartender looks at the first guy and says, "Superman, you can really be an ass when you're drunk."
(That's right, you're gonna work for your joke
)