That one song or soundtrack that whenever you hear it, fills you with a sense of wonder. That music that fills you with emotion.
Me, personally, would be "Beyond The Bounds" from Zone of The Enders. The Eshericks remix that came with the Limited Edition HD Collection is even better in that regard in my opinion, that song alone is reason enough for me to have bought that game.
Well, there's also every single song from NieR, that game was so amazing --- GT: Devilwillcry42 PSN: Raidoukuzunoha42 My name is Kanji Tatsumi, you said I like dudes, prepare to die.