"Fantaisie-Impromptu in C-Sharp Minor", by Frédéric Chopin, is a solo piano composition featured in "The Variable" in which it was played on the piano by Daniel Faraday, both as a boy and again in 2004. In the flash-sideways timeline, David Shephard performed this piece and had a copy in his room. ("Lighthouse") Also in the flash-sideways timeline, Daniel played the piece at Eloise Widmore's charity fundraiser. ("Happily Ever After") Image:Fan Imp Chopin.png