ADSR Sample Manager - A smart sample management tool for your DAW
EarMaster - Professional software for ear training and practical music theory on Windows and Mac.
Soundly - Functional music for better sleep, focus and relaxation
GNU Solfege - GNU Solfege is free music education software.
Resonic Player - Resonic is the planet's fastest audio and music player, browser, and sample manager, built around a big waveform view and a frequency analyzer.
Meludia - Listening exercises and to sharpen your ear and music theory skills