"He got that ambition, baby. Look in his eyes. This week he's moppin' floors, next week it's the fries."

Those Kanye West lyrics are from the 2005 smash "Gold Digger," but they might as well have been taken from the biography of Jeff Bezos. Before he was the founder and CEO of the Web's largest and most influential retailer, Bezos used to spend his days cleaning ketchup off the floor at McDonald's. The uber rich entrepreneur recalls his humble beginnings in a new book called Golden Opportunity: Remarkable Careers That Began at McDonald's.

"My first week on the job, a five-gallon, wall-mounted ketchup dispenser got stuck open in the kitchen and dumped a prodigious quantity of ketchup into every hard-to-reach kitchen crevice. Since I was the new guy, they handed me the cleaning solution and said, 'Get going!'" Bezos tells author Cody Teets. "I was a grill man and never worked the cash registers. The most challenging thing was keeping everything going at the right pace during a rush. The manager at my McDonald's was excellent. He had a lot of teenagers working for him, and he kept us focused even while we had fun."

And what advice does Bezos have for other young people starting out at the lowest rungs in the workforce who may dream of launching their own billion dollar company?
"You can learn responsibility in any job, if you take it seriously," he says. "You learn a lot as a teenager working at McDonald's. It's different from what you learn in school. Don't underestimate the value of that!"