Former Starbucks CEO Howard Schultz grew up in a Brooklyn housing project where crime was rife. His family was so cash-strapped that Schultz once sold his blood while studying at the University of Northern Michigan, and his parents sadly couldn't afford to attend his graduation ceremony.

After college, he worked as a door-to-door salesman before joining a European homewares company. One of its clients was a little-known coffee shop in Seattle called Starbucks. Not long after, Schultz took over the business and turned it into the global coffee chain it is today. He's currently worth $2.9 billion (£2.3bn).