The sky's the limit when a billionaire like Bill Gates goes on vacation. Not space, mind you--but let's be serious, it can't be long now. First up, a relaxing game of tennis in the morning before being helicoptered--not ferried--back to the superyacht you and your family have chartered to the tune of $5 million a week. Then, an exuberant jet ski around the $330 million boat with wife Melinda and children Rory, Jennifer and Phoebe, moored off the billionaires playground of Porto Cervo, Sardinia. The Microsoft founder and philanthropist--worth $76 billion--has taken time away from his busy schedule to relax with his family - renting The Serene, the 436-foot yacht of Stolichnaya vodka magnate, Yuri Scheffler, as a luxurious base.