For a number of years, the name Ken Griffin was attached to the title of Illinois' richest person. However, a couple of years back, Mr. Griffin (like many other Illinoisans) decided to move to Florida. By doing so, he became Florida's richest man, and a new person from a wildly successful family stepped up to become the richest person in Illinois. He also happens to be one of the youngest on the Forbes 400 Richest List.