Stewart joins charity trading day
Sean Bean, Idris Elba, Sara Cox, Cerys Matthews, Lisa Snowden and the Duke of Cambridge and Prince Harry also took part in the event at brokerage firm BGC Partners in London's Docklands. The company holds the annual Charity Day to raise money in memory of people who died in the attacks on New York's twin towers on September 11, 2001.
Comedian Jimmy Carr, the compere for part of the event, said: "They raise a phenomenal amount for 15 different charities. I'm not here with any one of the charities today, it's kind of the broad church.
"They do one dedicated day, which makes it a lot easier than doing it piecemeal through the year. I literally don't understand what they're doing. It looks like they're trying to land a plane on the screen, and then they're going 'Yeah, five two four'. It's like a different language. I've no idea what they're up to."
Radio presenter Lisa has been attending the charity day for the last six years and is raising money for Breast Cancer Care.
She said: "It's amazing that all these guys give up this day, 9/11, for the trades for all the guys they lost in New York. So many people come down. It's getting bigger and bigger each year. The guys make you feel like you actually know what you're doing in the trading world. I should know what I'm doing - I'm a little bit more au fait with the terminology - but everything happens so fast."
Actor Sean was on the trading floor to raise money for Sohana Research Fund, which helps people who have the incurable genetic skin condition recessive dystrophic epidermolysis bullosa.
The actor said: "It's something I've become quite close to over the years."
Asked about what the atmosphere was like at the charity event, he said: "It's quite informal. It's quite relaxed - a bit mad. I don't know what I'm doing but I think I'm raising money. It's quite an insight into an aspect of the financial world, and I don't make it out at all."
BGC lost 658 employees in the attack on the World Trade Centre 12 years ago, and its annual Charity Day, now in its ninth year, has so far raised more than 89 million dollars. All profits from the trades during the course of the day are donated to good causes.