And the richest man in the world is...

Bill Gates may not have had much of a pay rise this year but he did manage to add $2bn to his fortune to bring it up to $48bn and stay on top of the Forbes 400 list of wealthy Americans.

And, while being a dollar billionaire isn't what it used to be -- there are 313 on the list this year, compared to 262 last year -- Gates is a couple of lengths ahead of the nearest competitor, the legendary 'Sage of Omaha' investor Warren Buffet who has $41bn. And he is half the track ahead of number three Paul Allen, who sits on a pile of only $20bn, after dropping $2bn since last year.

This is the eleventh year on the trot that Gates has topped the Forbes list.

Once you strip out the five Waltons, the offspring of the founder of Wal-Mart, each of whom is reckoned to be worth $18bn, the next two billionaires on the list are also high-tech. Michael Dell comes in at number nine with $14.2bn and Larry Ellison is last of the top 10 with only $13.7bn.

Ellison's standing is particularly disappointing. Last year he was believed to be worth the same as a Walton, $18bn, but the decline of Oracle stock has brought his net worth down to a mere $13.7bn.

The new boys on the block, Google founders Sergey Brin and Larry Page, joined the list for the first time as joint 43rd with $4bn each. The youngest on the list, they are only just behind number 38, the long-established Jeff Bezos of Amazon.

The total net worth of the richest 400 Americans topped $1tn for the first time since the height of the dot-com boom four years ago.

Earlier this week, Microsoft revealed that both Gates and Balmer had kept their pay almost static at just over $900,000.