Record a melody as a MIDI file, right from the computer keyboard with no special hardware required.
Current work on the project is aimed at music analysis. Rhythm and harmony have completed subroutines. A future version of the program will analyze MIDI files, rate their musical value, and recombine them to produce new tunes.
CIOS Audio Core is the infrastructure and subsystem in Collective Intelligence Operation System. It is a cross platforms audio abstract interface, supports including Mac OS X, Linux, Android, iPhone OS and Windows 7.
Sculptor is a phase-vocoder-based package with real-time capabilites. You can use it to fiddle with soundfiles in the frequency domain, changing pitch and duration independently.