Eminem

When Eminem shared a stage with Marilyn Manson at the UK's Reading Festival in 2001, it felt like an unholy meeting of the two most dangerous men in popular music. But today's controversy is tomorrow's ennui, and Marshall Mathers' career faltered badly during the coming decade, for reasons both personal (he entered rehab in 2005 for dependency on sleep medication) and creative (2009's dire comeback album, Relapse). All of which makes it more remarkable that he's managed to turn things around, helped by the global success of Rihanna-featuring single 'Love the Way You Lie' in 2010. His first trip to Japan in nine years finds him just shy of his 40th birthday, and reportedly at work on an eighth, as-yet-untitled album.