Captain Chords - Write chord progressions in your favorite DAW
AIVA - The AI composing emotional soundtrack music
Odesi - ODESI is a music sketchpad that exports your projects to Audio and MIDI.
WolframTones - Listen to what I just found in the WolframTones music universe
Cthulhu - VST MIDI-FX plugin for harmonic inspiration
WaveBots Editor - Procedural music and sound maker that exports to Wav, MIDI, GoatTracker and much more.