Rod Stewart, Idris Elba, Anna Friel, Melanie Chisholm and Britain's princes William and Harry were among the stars who manned the phones on a trading floor in London on Wednesday (11Sep13) as part of a 9/11 charity event. A whole host of actors, musicians and royals joined the British leg of Cantor Fitzgerald's and BGC Partners' annual Charity Day, which commemorates the victims of America's 2001 terrorist attacks. As part of the event, famous faces man the phones and the day's profits are donated to good causes. Stewart was there with his wife Penny Lancaster while Prince William and his brother Prince Harry also took calls during the star-studded event. Other celebrities who turned out for the day's trading in London included Sir Ian McKellen, Sean Bean, David Hasselhoff, Cerys Matthews, Danny Dyer and Ashley Roberts, while on the other side of the Atlantic, Mariah Carey's husband Nick Cannon, Sean 'Diddy' Combs, actor Zachary Quinto, and The Sopranos stars Edie Falco and Bobby Cannavale turned out in New York. Last year's (13) event raised millions of dollars for good causes worldwide.