21. George Foreman

Huge boxing legend, George Foreman won an Olympic gold medal and has been called the eighth greatest heavyweight boxer of all time by the International Boxing Research Organization. He quit boxing after he reached a certain age, and turned to completely different hobby-turned-to-profession: grilling!

His healthy lifestyle leads the famous appliance maker to hire him as a promoter for the George Foreman Lean Mean Fat-Reducing Grilling Machine, which has sold over 100 million units. The grilling machine became so popular that it is estimated that Foreman earned around $200 million from the deal, probably more than he ever earned during his sports career.