Impro-Visor ("Improvisation Advisor") is a software tool designed by musician and computer scientist Bob Keller to help jazz musicians work out, hear, and record solo ideas, including studying the work of others. It provides a notation capability for lead

CyberBass is a free service that provides online MIDI accompaniments to many standard choral works. In addition, separate MIDI files for each individual voice part are available as an aid to learning and practicing individual parts.

Sonic Amigos specializes in software for the Macintosh and iPhone platforms. Formed in 1999, Sonic Amigos strives to provide the Macintosh and iPhone communities with compelling, useful, and fun software. Software includes PolyPhontics and PolyPhontics GB (GarageBand) that allow one to create software instruments. If you like to download MIDI files from the web and import them into GarageBand or Logic, PolyPhontics MIDI Utilities may be of use.

Audiveris is an open-source Optical Music Recognition software which processes the image of a music sheet to automatically provide symbolic music information in MusicXML standard.