Jean-Claude Gandur

Having netted $1.5 billion in the sale of his Addax Petroleum to Sinopec in 2009, Gandur could have retired to focus on adding to his world-class collections of art and Egyptian antiquities. Last March Gandur donated $20 million to Geneva's art and history museum and pledged to house many of his 800 artefacts there--including 250 works of post-war abstract art. But instead of slowing down, the oil tycoon is looking to get back in the game, launching Oryx Petroleum to vie for Nigerian oil fields being shed by Shell. Gandur's trading group already sells fuels throughout sub-Saharan Africa, and in Sierra Leone has launched a $400 million project to grow sugarcane for ethanol.