The Unheard Beethoven
This site "endeavors to make all of Beethoven's unrecorded music readily accessible to the public. "
As an unexpected plus, the website also illustrates that copyright laws can be asserted in reasonable and socially useful ways:
"While the Unheard Beethoven website is dedicated to the dissemination of Beethoven's work as widely as possible, the content of this site and all MIDI files contained on this site are copyrighted by Mark S. Zimmer and/or Willem (aka xickx). Fair use of these MIDI files is encouraged; we ask, however, that in connection with any such use that the arranger of that particular MIDI file be credited and the URL of the Unheard Beethoven website be listed. Bulk download and copying and/or distribution of the MIDI files on this site is strictly prohibited. No more than 25 MIDI files may be downloaded or copied in any one day by one entity without the permission(s) of the copyright holder(s).