Some of the biggest names in music took to the stage at Live Earth, the controversial anti-global warming event billed as the "greatest show on earth". Celebrities took the stage in seven continents on Saturday (July 7, 2007) to raise awareness about climate change. Live Earth featured concerts in New York, Washington, Sydney, Rio De Janeiro, Johannesburg, Tokyo, Shanghai and Hamburg. Akon and Alicia Keyes were among those rocking the New York area at Giants Stadium in New Jersey. UB40 played Johannesburg, while Pharrell Williams wowed fans in Rio. Stars also included Ricky Gervais, Geri Halliwell, comedian Chris Rock, former tennis hero Boris Becker, Sex and the City and Desperate Housewives star Kyle MacLachlan and actress Thandie Newton took to the stage to talk about global warming and introduce the acts. Organisers say the power used to put on the Wembley concert is being sourced from renewable energy. The audience is being asked to commit to Live Earth pledges, which include using energy-saving lightbulbs, and turning off computers when not at work. Proceeds from the Live Earth spectaculars benefit climate crisis charity The Alliance for Climate Protection, founded by Al Gore. Plastic water bottles and cups were being used at Wembley, and the audience were urged to recycle them in bins at the stadium. But some were just lying around in ordinary bins.