Countries that billionaires could buy

Dubai: How about a country? A quick glance at the CIA Fact Book suggests the individual fortunes of many Forbes 400 members are as big as some of the world's economies.

Bill Gates, America's richest man with a net worth of $50 billion, has a personal balance sheet larger than the gross domestic product (GDP) of 140 countries, including Costa Rica, El Salvador, Bolivia and Uruguay.

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The Microsoft mogul's visionary's nest egg is just short of the GDP of Tanzania and Burma.

Pierre Omidyar, founder of eBay, the world's biggest auction marketplace, could theoretically control Somalia's market with his $5.5 billion fortune.

George Lucas, the famed Hollywood director behind the Star Wars and Indiana Jones franchises and ILM, the world's most bankable special effects shop, has a $3 billion fortune, making him worth as much as the GDP of Guyana.

Forbes 400 members with net worths just under $1 billion still possess fortunes that could operate the economies of significant fractions of the globe.