Inspired by Bach's Well-Tempered Clavier, Chopin wrote a set of 24 preludes for piano each in a different major or minor key. The No. 20 Prelude in C minor is sometimes called the Chord Prelude because it consists mostly of a sequence of chords, with a characteristic descending pattern in the bass. There is a lot of modern-sounding chromaticism (and drama) in this progression of chords, and perhaps that's why these have been borrowed by composers including the song-writer Barry Manilow in his song "Could It Be Magic". You can download this prelude as PDF format sheet music, or as a midi or mp3 file using the links on the left-hand menu.