Seeing as Hathen has long since beaten me to all the other songs that popped into my head, I'll just put this here:
Broken Blade /
Yoshihisa Hirano -
Fight against DestinyActually, Broken Blade has quite a bit of good music, but that's my personal favorite. Can't wait until the TV adaption comes out next month.
The HeroesNot sure if it counts, and it's kinda the same song, but more opera-ish.