Making billions of dollars is no easy task. Even as children, many billionaires sacrificed the pleasures of youth in the pursuit of money. So, what happens when they reach their goal of having endless money? For billionaires that are young at heart, they pursue the dream of "Never Growing Up." On this week's episode of The Filthy Rich Guide, we explore how the super-rich try to recapture their youth. For some billionaires, it means living out childhood fantasies. Bill Koch loved the Wild West so much that he spent $3.1 million to buy his very own western style ghost town. For others, it's about searching for ways to live forever.