If having money in the bank eases worries about essentials, such as a roof over your head, being a billionaire means they can be pieces of art unto themselves.

Bill Gates, the perennial top-ranked billionaire now worth $56 billion, has a 66,000-square foot compound built into a Medina, Wash., hillside.

While the home, just outside Seattle, couldn't fit every Microsoft Vista buyer, the 1,000-square foot dining room, domed roof library with secret chambers, 60-foot pool and five acres of space could host quite a launch party for future editions.

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The London home of steel baron Lakshmi Mittal, ranked No. 5 on our list, is tucked between Kensington Palace and the Sultan of Brunei's spread. In 2004 Mittal paid $128 million for the townhouse, the highest single-home buy of all time, and situated in what is known as "Billionaire's Row."

Mittal's mansion has garage space for 20 cars and is embellished with marble taken from the same quarry that supplied the Taj Mahal.

But if, like the average American, your home tops out at 2,000 square feet, has three bedrooms and is sided with vinyl or aluminum, take heart; some billionaires are right there with you.

Midwestern Modesty

Berkshire Hathaway mastermind Warren Buffett, No. 2, has lived in the same house for the last 50 years. He beds down in a 6,000-square-foot gray stucco home in Omaha's Happy Hollow neighborhood that he originally bought for $31,500.

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Perhaps because much of his fortune is earmarked for a charity (in June, Buffett signed philanthropic commitment donations for more than $30 billion, representing over 85% of his net worth), he lost a challenge to a 2003 appraisal valuing the home at $700,000, contesting that it was worth a mere $500,000.

Even the luxury of a custom license plate reading "Thrifty" was too much for Buffett. In September he auctioned off the 2001 Lincoln Town Car that bore it to benefit charity.

Small-Town Boys

While money means you can reside anywhere in the world, many billionaires prefer the comforts of home. Microsoft co-founder Paul Allen, ranked No. 19 with a net worth of $18 billion, lives on Mercer Island, Wash., a ferry ride away from his hometown of Seattle. Not only that, the 10,000-square-foot mansion sits on a compound that also has a house for his mother.

Michael Dell, too, prefers the familiar. Ranked No. 30 with a net worth of $15.8 billion, the Dell founder, who this year resumed control of operations at his self-named enterprise, lives in Austin, Texas, only a few miles from the university dorm room where he started the company.

Worldy And Wealthy

That's not to say billionaires don't globe-trot. Many keep second, third, even fourth residences all over the world. One particular commonality is New York City. Allen and Viacom chief Sumner Redstone, No. 86 with a net worth of $8 billion, are two of many who maintain secondary homes on New York's East Side.

Here, they join many illustrious full-time residents, such as David Koch (No. 49, with a net worth of $12 billion), who lives in an 18-room duplex in the exclusive 740 Park Avenue building, and Michael Bloomberg. The city's mayor (No. 142 with a net worth of $5.5 billion), who also owns homes in Bermuda, London and Vail, Colo., de-stresses in a five-floor, 7,500-square-foot townhouse a half-block away from Central Park. He also owns homes in Bermuda, London and Vail, Colo.

Another benefit of money? No mortgage payments, should you choose. If you've got the money to play the top-flight real estate market, there's no need to bother with borrowing rates. Just pay cash in full.

And as anyone who has bought a home can attest, not having to deal with banks may be the greatest luxury possible.

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