The Top Ten
William Gates III
Net Worth: $46.5 bil , Company : Microsoft
Warren Buffett
worth : $44 bil
Lakshmi Mittal
Net Worth: $25 bil
Carlos Slim Helu
Net Worth: $23.8 bil
Prince Alwaleed Bin Talal Alsaud
$23.7 bil
Ingvar Kamprad
$23 bil
Paul Allen
$21 bil
Karl Albrecht
$18.5 bil
Lawrence Ellison
$18.4 bil
S Robson Walton
$18.3 bil
Out of the top 10 three are software giants. Fastest growing billionares not listed in the list are India's Reliance Group [Ambani brothers ($7.5) their main field is communication, followed by Tesco Groups main field is super market.
Who knows there might be a few billionares in joeusers as well, no Idea about Joeuser's admin wealth might be in top 100 [Just kidding]
Thanks to Mastto, Forbes & Google for the research.