He bought a six-pack of an energy drink. He'd never tried it before. The ads promised four hours of energy. He drank the little bottle. He waited for the energy to kick in. He needed to cram for a test the next morning. Nothing happened. I can't wait all night, he thought. He drank another bottle. This'll give me EIGHT hours of energy, he thought. That meant he'd be up until 4 a.m. Nothing happened. He drank another bottle. Now I'll be up till 8 a.m., he thought. But that was no good, because the test started at 8 a.m. He drank another bottle. He started studying for the test. He couldn't concentrate. His eyes felt like they were crossing. His head felt like it contained a live electric wire. He couldn't study, and he couldn't sleep. Somehow, he managed to pass the test. No more cramming, he promised himself.