The 10 Richest People You've Never Heard Of

If you liked building things as a child, there's a good chance you'll recognize his family's business.Kristiansen's grandfather founded the Danish company Lego in 1932. At first, his grandfather crafted wood toys in a carpentry shop but in 1949 the company invented what would become its most famous product. At the time, the stackable plastic pieces with studs on top were called the Automatic Binding Brick.Today, we simply call them Legos and the company is the world's sixth-largest toymaker by sales. The company's success led us to peg Kristiansen's net worth at $6.5 billion in March.