Mary and Gary West are probably the richest American couple you've never heard of--and they did it the new-fashioned way. They took their company public, got rich, then took it private again and got richer still. The couple's business, West Corporation, provides large corporations with a variety of services--call centers, teleconferencing, even bill collection--and also runs the technology backbone for the national 911 system. In 2006, the company's top line exceeded $1.8 billion, up from $317 million in 1996, the year of its initial public offering. Timing the private equity bubble adeptly, the Wests closed a deal at the end of 2006 whereby two large funds bought up 66 percent of West Corporation, taking it private. For the founders, it was quite a payday: $1.45 billion plus 23 percent of the company. So how are the Wests spending their newly liquid fortune? First, they plan on funding start-ups in their hometown of Omaha, starting with a payment-processing company called Planet Group, in which the couple recently invested an undisclosed sum. Meanwhile, the Wests continue to indulge their passion for horseracing. Though their Kentucky Derby mounts have run poorly to date, they own several fine horses, including High Limit, Dollar Bill, and a 1999 stakes winner named, yes, Entrepreneur.