Franz Schubert wrote a real earworm with his lieder, Die Forelle, or The Trout. In fact, it was such a catchy tune that a wealthy patron suggested that perhaps Schubert could create a set of variations with it. And Schubert did--in five different pieces. The first time was Schubert's Piano Quintet in A Major nicknamed, of course, the Trout. Rather than the usual line up of piano and string quartet, Schubert shook up the formula a bit, dropping the second violin in favor of a double bass. And it all worked; to this day it's a favorite in the world of chamber music.