Odesi - ODESI is a music sketchpad that exports your projects to Audio and MIDI.
Captain Chords - Write chord progressions in your favorite DAW
Waveform - Full-featured, cross-platform Digital Audio Workstation built for inspiration and composition
Helio Workstation - Cross-platform lightweight speed-painting tool for creating music.
Cthulhu - VST MIDI-FX plugin for harmonic inspiration
Plugin Boutique - Inspirational MIDI effect that makes finding chords and progressions intuitive and fun