J.S. Bach's Toccata and Fugue in D Minor, BWV 565, is perhaps the single most recognizable piece of pipe organ music in the western world. If there is an Ominous Pipe Organ in a Haunted House, it's probably playing the opening bars of the Toccata and Fugue in D Minor. A fully orchestrated version served as the centerpiece of Fantasia's first segment. The intro was remixed into the intro to the title screen theme of the Dr Brain series.