Orisinal Games
A huge assortment of cute and mellow (if still time-based) games including ones where you guide a puppy across a peaceful landscape, collect marshmallows with mice, or have giraffes kiss each other.
http://www.ferryhalim.com/orisinal/
Virtual Zen Garden
Rake the sand & landscape in a virtual garden based on those used by Zen Buddhists for meditation.
Stress is relieved by methodically arranging stones and raking patterns in the sand which relaxes & quiets the mind by focusing on repetitive physical movements.
http://www.japangarden.co.uk/Zen-Garden-p-16.html
https://scratch.mit.edu/projects/39009/
Zen Photon Garden
Relaxing interactive raytracer. Create your own photoreactive patterns by dragging your mouse or touchpad.
http://zenphoton.com
Silk
Interactive generative art. Create your own colorful fractal patterns by clicking and dragging your mouse across the screen.
http://weavesilk.com/
Neon Flames
Another interactive art creation site, create galaxy-like patterns with a few flicks of your mouse.
https://29a.ch/sandbox/2011/neonflames/
Kaleidoscope Creator
Slowly build up your own kaleidoscope patterns one component at a time.
http://www.zefrank.com/byokal/kal2.html
Meditation Flowers
Influence the growth and development of these psychedelic flowers by singing to them. (Requires the use of a microphone attached to your PC)
http://www.zefrank.com/meditation_flowers/
Nature Sounds for Me
Compose/mix your own set of calming ambient nature sounds to suit your own personal tastes.
http://naturesoundsfor.me/
Samorast
Slowly explore a surreal asteroid-based universe by wandering around and poking through anything interesting that crosses your path.
http://amanita-design.net/samorost-1/
Echogenesis
A calming & immersive experience of exploring different natural worlds. Roam freely and enjoy both visual and audio interactions.
http://www.echogenesis.com/
Mirror: https://www.newgrounds.com/portal/view/314432
Flow
Float around as a tiny geometric creature and watch your evolution as you explore and consume other tiny organisms.
http://interactive.usc.edu/projects/cloud/flowing/
Candy Box
Collect, hoard, and go on epic quests for candies in this cute ASCII RPG game.
http://candies.aniwey.net/
http://candybox2.net/
Virtual Bubblewrap
Pop those bubbles! Almost as therapeutic as the real thing.
http://www.virtual-bubblewrap.com/popnow.shtml
Bejeweled
Simple but addictive puzzle game of swapping jewels into patterns of 3 or more. An old and well known classic for relaxing the body while exercising the mind.
http://bejeweled.popcap.com/html5/0.9.12.9490/html5/Bejeweled.html
Poppit Stress Buster
A cross between Virtual Bubblewrap & Bejeweled... what's not to like? Pop those balloons in patterns of 3 or more
http://www.best-flash-games.net/puzzle-games/poppit-stress-buster.html
Stress Reducing Mah Jong
Distract oneself from stress by focusing your mind & concentration on a puzzle-type game such as Mah Jong. This particular version from WebMD gives health & stress related tidbits as prizes for each step in unlocking the puzzle.
http://www.webmd.com/balance/stress-management/mah-jongg-game
Tetris
One of the oldest games still in circulation, studies have indicated that playing this can help with PTSD and other types of intrusive or stressful thoughts.
http://www.freetetris.org
http://www.tetrisfriends.com/
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