Larry Ellison

Even before buying Lanai, the sixth-largest of the Hawaiian Islands, Larry Ellison was spending money like few other CEOs in America.

In the mid-2000s Ellison, the founder of the computer behemoth Oracle, commissioned what was then the biggest yacht in the world, the 452-foot Rising Sun, at a reported cost of $270 million dollars. (He later sold it and has since bought another, smaller yacht at around 250-feet).