Rihanna: Last Girl on Earth Tour With Special Guest Ke$Ha August 22, 2010

Rihanna, one of the most well-known pop singers in the world, has achieved six number-one singles on the Billboard Hot 100 chart including, 'Rude Boy,' Umbrella,' 'Disturbia,' and 'Don't Stop the Music.' She won two Grammys at the 2010 awards and her current tour is titled, 'Last Girl on Earth Tour.'