19. Hiroshi Mikitani
Net worth: $8.7 billion
Hiroshi Mikitani is the chairman and CEO of Rakuten, Japan's largest e-retailer. Recently, Mikitani acquired U.S. online rebate site Ebates for $1 billion. The site allows users to earn cash back when buying goods at stores. The 50-year-old left Japan to attend Harvard Business School in 1993, where he earned his MBA. After working for Industrial Bank of Japan and later starting his own consulting group called Crimson Group, Mikitani founded Rakuten with a small group in 1997 with $250,000 of their own money. Today the company generates over $5 billion annually. Forbes ranks Mikitani as the 151strichest person in the world.