US actor Will Smith performs at the 46664 concert in honour of Nelson Mandela in Hyde Park, London June 27, 2008. The event was organized to raise funds for Nelson Mandela's HIV/AIDS "46664" campaign, named after his prison number. Exactly 46,664 people were expected to attend the event, which also celebrates the former South African president's 90th birthday on July 18. [Agencies] Will Smith and Tom Cruise have autograph signing competitions. 'Hancock' star Will has revealed he and his close friend Tom always try to outdo each other by spending the most time with their fans on the red carpet. Will said: "It's hard to beat that dude. He has another gear. He did two-and-a-half hours in France for 'Mission: Impossible' on the red carpet. Now when I go to France, people will say, 'You know, Tom was out here for over two-and-a-half hours.' " The 39-year-old actor also revealed playing boxing legend Mohammad Ali in 2001 hit 'Ali' inspired him to have more confidence in himself. Will - whose performance earned him an Oscar nomination - explained: "When I was doing 'Ali', I realised that he kept saying, 'I'm the greatest, I'm pretty,' to make himself believe it. He doesn't believe it, but he was dealing with racism. He was reacting to pain and rejection. He said it so much that he started to really believe it. That is what I've tried to do for myself."