LONDON (Reuters) - The Beatles have gone underground with a dance mix. "Free Now" is the first original work by the Beatles since Paul McCartney, George Harrison and Ringo Starr regrouped in 1995 to record the John Lennon song "Free as a Bird" in memory of their slain colleague. McCartney has created what he called "a manic Beatles single" with out- takes from old recording sessions, unheard cuts of Beatle guitarwork and studio chats among the "Fab Four". It will only be available as a promotional single for disc jockeys and will be released as part of the Liverpool Sound Collage CD that is being put out by Hydra Records on August 21. "It is a new little piece of The Beatles," McCartney said of the club mix.