Although it could have changed since, back in March of this year, Mexian Carlos Slim was named as thew worlds richest man with a fortune of $55.3 billion
http://funadvice.com/r/14lo3p2biks
Mr. Slim must have done well this year, he's listed at $60.6 billion now. :)
according to the top ten list it's Carlos Slim HelĂș. net worth is $53.5 bil