More of Yuki Kajiura works:
Parting Song From Pandora Hearts
Preparation From Pandora Hearts
Aura From .Hack//SIGN
In the Land of Twilight, Under the Moon From .Hack//SIGN
Key of the Twilight From .Hack//SIGN
And here is one of my Favorits:
Fake Wings From .Hack//SIGN and A Thousand and One Nights from .hack//LIMINALITY. Here is the male version of it as a bonus: A Thousand and One Nights (Male Version)

And another song from Yamazaki Masayoshi after I watched 5 centimeters per second a while back. Dang I like this song: One more time,One more chance