The world's richest man, Bill Gates, has admitted there is no computer big enough to store the financial history of his wealth.
The Microsoft founder yesterday admitted that the US tax office has to store his financial data on a special computer because his fortune is so vast.
"My tax return in the United States has to be kept on a special computer because its normal computers can't deal with the numbers," he said at a Microsoft conference held in Lisbon.
"So I am constantly getting these notices telling me I haven't paid something when really it is just on the wrong computer.
"Then they will send me another notice telling me how bad they feel that they sent me a notice that was a mistake."
According to the latest Forbes magazine, Gates's has an estimated fortune of $US47 billion ($62.88 billion).
Gates and his wife Melinda have created the world's biggest charity with an endowment worth $US29 billion ($38.8 billion).