Bach's organ piece, with a scrolling score. Production notes for this piece are here:

http://www.musanim.com/ProductionNotes/ToccataAndFugueInDMinor.html

This type of display can be generated from any MIDI file with this tool:

http://www.musanim.com/player/

Note: If you have trouble with sync or audio quality, download the original (m4v) version.

There's a description of this piece in the viewer guide for the video (DVD) that contains it:

http://www.musanim.com/pdf/ViewersGuideMAM1996.pdf