Live music and an artistic masterpiece: that is what Billygoat has to offer its audiences. Both David Klein and Nick Woolley create animated art films, which they show to audiences on full-size screens. The duo writes an original score to perform along side the live showing of the movie. They use instruments ranging from the harp, accordion and electric guitar to entertain their fans. Billygoat will perform at Williamsburg Music Hall on Jan. 20 and at Bowery Ballroom on Jan. 21.