Songwrite is a tablature editor. It supports many string instruments in addition to traditional staff notation. You can edit tablature (guitar, bass, banjo, etc.) and staff notation, add lyrics, create your own songbook, play your partitions, print your partitions and your songs, automatically convert staff notation to tablature and vice-versa, export songs to many formats (PDF, MIDI, ASCII tablature, GNU Lilypond, LaTeX, PostScript, etc.), and import Guitar Pro 3/4 files (experimental).
Audiality is a highly scalable and portable audio engine and synthesizer. MIDI files are used in combination with scripting and modular synthesis, to minimize file sizes and maximize flexibility. Audiality can be used as a music and sound effects player in multimedia productions, or as a realtime MIDI synthesizer.
FrAid (Fr[actal] Aid) is a programming language that is appropriate for mathematical computations, visualization, batch processing, and more. It features both a standalone application that provides a programming environment for the language and a system for integrating the language with Java. The Java interface allows mathematical equations and formulas to be used with Java code, making it easier to process numerical computations, symbolic computations, imaging, CAD, and more.
The Non Sequencer is a powerful real-time, pattern-based MIDI sequencer for Linux. It fills the void left by countless DAWs, piano-roll editors, and other purely performance based solutions. It is a compositional tool that transforms MIDI music-making from a complex nightmare into a pleasurable, efficient, and streamlined process.
Impro-Visor is a music notation and playback tool for helping jazz musicians learn to improvise. It features a notation GUI, automated playback of chords and rhythm using MIDI, and improvisation advice provided in a variety of ways, including being able to improvise jazz itself. Data are stored as open-format text files. MIDI and MusicXML export are also available.