We would say that flOw makes a good case for the "video games as art" discussion, but it's tough to quantify it as a game to begin with. Originally an MFA thesis by USC School of Cinematic Arts game design graduate Jenova Chen, flOw has appropriately evolved from a simple, accessible design philosophy into a popular Flash title, and has now made its way onto Sony's Playstation Store as a downloadable title. It has been retooled and reworked to add depth and take advantage of the PS3's 1080p, 5.1 surround capabilities and motion-sensitive controller, and has thankfully lost nothing in the transition. It's a simple concept, executed with an elegance and subtlety that anyone can relax and enjoy.
You begin your aquatic adventure as a very simple organism, made up of what looks like a mouth, tail, and a few bits and pieces holding you together. You manipulate the swimming direction of your creature with the motion-sensing component of Sony's Sixaxis controller, and can press any button for a short boost. It takes a couple of minutes to get a feel for controlling your little buddy, but quickly becomes second nature.
The world of flOw is comprised of glowing, softly lit layers of water, different depths inhabited by organisms resembling fish, amoebas, jellyfish and all sorts of imaginative creations in between. You can "eat" anything smaller than yourself, which contributes to the growth and evolution of your body - little bits and pieces will be added, colored or lit up on your creature, serving as an indicator of sorts of your progress and strength. If something larger than you hits one of your pieces, you will likely lose it and be kicked back up to a higher depth. Conversely, some of the more complex creatures you'll face require certain parts to be devoured first before they break into smaller schools of critters. Your interactions with the other life forms are deeper than you'd expect in that regard, but it can be a bit unclear who is winning a conflict until the end.
Each level of water contains a set amount of edible creatures, as well as two very special ones - a red one that will take you down to the next depth, and a blue one that will take you back up. Eat enough and dive deep enough and you'll eventually change forms completely (there are five different forms to be unlocked), and open up a new set of levels to play through. You can technically see all there is to see in about an hour, but it's an experience you'll likely return to to show friends (up to four people can play) or when you just need to relax and absorb yourself in something beautiful.