8. Inventor
Digital TrendsCase Study: James Dyson
Country of Citizenship: United Kingdom
Net Worth: $4.2 billion (£3.3 billion)
Born in Cromer, Norfolk, James Dyson helped design the Rotork Sea Truck, a flat-hulled, high-speed watercraft in 1970 while studying at the Royal College of Art. His first original invention, meanwhile, was the Ballbarrow which was a modified version of the wheelbarrow. Dyson, though, is probably best known for inventing the Dual Cyclone bagless vacuum cleaner and the Airblade hand dryer.