Beethoven's notoriously difficult, groundbreaking Ninth (once called "the hammer that finally killed classicism") was his first symphony in more than a decade. It was also his last. Incredibly, Schubert, Dvorak, and Vaughan Williams (among others) also died after composing a ninth symphony.

Indeed, musicologists joke about a 'ninth symphony syndrome': Mahler, superstitious about his ninth, promptly attempted to complete a tenth -- and promptly died. Bruckner, despite numbering his first two symphonies 00 and 0, also died while composing his ninth. And Sibelius? He wisely stopped after his eighth -- and went on to live another 33 years.