#4 Amazon's Jeff Bezos: grill cook at McDonald's

The founder and CEO of Amazon.com worked as a grill cook at McDonalds, because he needed a summer job.

"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!'” according to Cody Teets' book "Golden Opportunity: Remarkable Careers That Began at McDonald's":

"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."

#3 FireEye's David DeWalt: telemarketer for Oracle

DeWalt, the former McAfee CEO, now heads security startup FireEye, which he joined in 2012. He’s graduated from the University of Delaware in the 1980s with a B.S. in computer science. DeWalt’s first job was as a telemarketer for Oracle and his job duties included making some 500 cold calls every week, according to a profile on the University of Delaware website.

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