The music mogul took poll position after earning a staggering £50 million in the last year - £15 million more than Cowell's earnings in 2008.
His latest accolade is proof the 50-year-old star's success shows no sign of ending anytime soon. A $1 billion deal with Sony will see him take part-ownership of his label Syco, entitling him to 50% of its profits, the ability to sell the X Factor and Britains Got Talent formats to even more countries (making Cowell an estimated £500 million by 2012), and gives Cowell joint control of artists produced by the shows, including Leona Lewis, Alexandra Burke and Susan Boyle, whose debut album was the fastest-selling record in history.
22,000 people agreed to clean toilets for WiFi because they did not read the terms.
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The rounded sleeping capsules send guests drifting into ocean before arriving on desert island by morning.
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Scientists are appealing for more people to donate their brains for research after they die.
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Lunar mission scheduled at the end of 2017 could find out if beer can be brewed on the moon.
A bottle used to teach children how far litter can travel ended up on Scottish beach after 8,700-mile journey.