Yesterday, Today from RahXephon, Composer - Ichiko Hashimoto
This piece will be really nice to play on a calm day. I would really appreciate it if you can provide us with this piece. Thank you if you do post it up. Thanks.

Hey do you know the title of the song in rahxephon where Quoan plays the piano?

I've got a few on my site-- see if you find what you want here...

http://josh.agarrado.net/music/anime/master-index.php?q=rahxephon