Clone Hero - Clone Hero is a free rhythm game, which can be played with any 5 or 6 button guitar controller...
Headspace - Meditation made simple. Brilliant things happen in calm minds.
Frets on Fire - Bonus content.
Calm - Calm.com can help you reduce stress and increase calm.
StepMania - Rhythm game for Windows, Mac, and Linux.
Medito - 100% Free Meditation App that will improve your Mental wellbeing with the help of Guided Meditations, Breathing Exercises, Mindfulness Practices, Relaxing Sounds, and more.