With a net worth of $81.5 billion, Microsoft cofounder Bill Gates is the richest man in America. It shouldn't be too surprising that one of the wealthiest people in the world also has an insanely extravagant home. It took Gates seven years and $63 million to build his Medina, Washington estate, named Xanadu 2.0 after the fictional home of "Citizen Kane"'s Charles Foster Kane. At 66,000 square feet, the home is absolutely massive, and it's filled with high-tech details. We've rounded up some of Xanadu 2.0's most over-the-top features here. 1. It's worth at (5 comments)