Last.fm is a UK-based Internet radio and music community website, founded in 2002. It claims over 21 million active users based in more than 200 countries. On 30 May 2007, CBS Interactive acquired Last.fm for £140m ($280m USD). Using a music recommendation system called “Audioscrobbler”, Last.fm builds a detailed profile of each user’s musical taste by recording details of all the songs the user listens to, either on the streamed radio stations or on the user’s computer or some p…