While an investment manager offers little to the value of the businesses they trade stocks in, many demand 2% or 3% commissions and fees.

Mr Buffett, whose estimated wealth of $29bn puts him second only to Bill Gates in lists of America's richest people, is fabled as an investment guru.

Buy well and sit back

The 'Sage of Omaha' showed his power to move markets during last month's visit to London when he hinted he was on the verge of investing in a UK blue chip company.

Wild speculation followed with a succession of companies ranging from British Airways to Marks and Spencer seeing their market value rise by millions on the belief they may be about to receive the Buffett approval.

He is known for investing in companies he likes and then holding the shares indefinitely.

Mr Buffett offers some share advice himself, for free: If people want to invest on the stock market, they should learn about a business, its management and project earnings into the future.

If all appears positive then they should buy the stock and sit back.

Those who invest in mutual funds should make certain the fees charged are not too high and should give up hope their investment will do better than average.

"The average investment manager adds nothing, " he said.

"He subtracts something from your investment performance. It's almost unique among professions that I can think of."

Thousands turn out

Mr Buffett was speaking as an estimated 15,000 shareholders in his own investment fund, the Berkshire Hathaway company, arrived for the annual three day gathering of stockholders.

His company owns shares in businesses such as insurance giants General Re and Geico, Coca-Cola, Nebraska Furniture Mart, The Washington Post, and International Dairy Queen.

And Mr Buffett shuns Internet stocks, because, he says, he does not understand the industry.