Microsoft founder Bill gates has remained as the richest man in the world for yet another year, giving him 13 years at the top. Gates himself is worth an impressive $56 billion, up $2 billion from the year before. Warren Buffet holds the second spot with $52 billion, whilst Carlos Slim Helu is just behind on $49 billion. Although Gates' wealth increased less than it has done in previous years - Windows Vista may help to line his pockets a little more after the huge development costs stalled Microsoft's profits for a short while - at 50 years of age, he's still well below the average billionaire which is 62 years old. It's also worth remembering that Gates has donated billions of dollars to charity, and him and his wife even set up their own charity known as the Bill & Melinda Gates Foundation.