If haven't played Chime, it was a small, downloadable musical puzzle game from years ago. It's generally compared to Lumines, the closest thing to it. But Chime was relaxing and trippy where Lumines was stressful and hectic. It was made by Zoe Mode for an initiative called OneBigGame, which game all the money for Chime to charity for the first year of its existence. Since Chime was only $5 dollars, it was an even easier decision to make. I loved it. It only had, like, three or four levels, but I played a bunch of it.
In Chime, you're building the musical track you're listening to, one element at a time, based on grid coverage. The effect was amazing. It starts ambient and relaxing and chill. But by the end, it gets to be euphoric if you've done well enough. The music choices and how they cut up the tracks to make this mechanic possible is the star of the show here.
BTW: That Chime demo doesn't play in Chrome. It uses a Unity browser plugin.