HarmonEye lets you see what you hear. A unique software application that looks like a retina of the eye, HarmonEye listens to music and displays the chords and tones being played. Any audio. In real-time. You can see the melody, chords, and key of your favorite songs. Include the nuances, like a singer's vibrato. It's easy to write it down or just stare at it for hours, and you will be amazed at your absolute pitch.
The software is free but it is donationware. To support development, please consider donating.