Electroplankton. It's not a game, precisely, though you do play with it (or on it, or through it...). Essentially, it turns your DS into a music creation tool -- but that's not quite right either, since you create rich and colorful visualizations as you play, and that's a huge part of the experience. So I think Nintendo has created a new category; MusiCreatiVisual? Kudos to the spunky game company. 

I was thrilled when the title arrived yesterday, and I spent an absorbing hour and a half last night just noodling around with the different plankton types; there are 10 of them, and each makes sounds in a novel way. (Pictured is Lumiloop; you trace the circles with your stylus at different speeds, and they emit varied colors and tones.)

In the booklet that comes with Electroplankton, you'll find a charming letter from its creator, media artist Toshio Iwai. At different times in his life, he variously used and loved a microscope, a tape recorder, a synthesizer, and a Nintendo NES. These devices were the combined elements that sparked the idea.

Electroplankton will be available online and at the Nintendo World store on January 9, for $34.99.