Forgive the double post, wanted to comment on my direction for this challenge. Wasn't really planning to enter this one, but an idea hit me that's just too interesting to ignore.
I'm a huge fan of Ambient music (it's especially good when you're working), and the 'Father' of Ambient music is Brian Eno, who defines Ambient Music as existing on the "cusp between melody and texture."
The story goes that Eno, while crossing a street, slipped and fell into the path of an oncoming taxi. While recovering from his injury, he was laid up in bed with very limited mobility, and would spend hours listening to records his friends would bring him on their visits. One day, a friend left a record of Harp music playing, but the volume was turned so low that it was barely audible. Too weak to cross the room, Eno was forced to listen to the record just barely audible.
"At first I thought, 'Oh God, I wish I could turn it up,'" Eno remembers. "But then I started to think how beautiful it was. It was raining heavily outside and I could just hear the loudest notes of the harp coming above the level of the rain." As he listened, Eno decided that this "melted-into-the-environment quality" was what he wanted in his music and his life.
So, what I'm kind of playing with now is a game that blends music with the quantity of space; maybe you define the size and shape of a room by dropping musical tones into emptiness, the colors and textures of the space by the pitch, and the furnishings and decor by the various melodies that weave subtly through the space.
Ambient music is meant to be very subtle; it's the concept of giving a space a harmony and mood via sound. So... I'm toying with ideas in that respect.