Music is greatly situational and most songs become powerful when together with the scene they were written for. Below a few that (even without the actual scene to support it) will show you how powerful songs can be. Most of these pieces are created by Japanese musical masterminds.
Im sure someone already posted this but here are my personal thoughts on this beautiful melody.
It captures the essence of elfen lied, the sheer amount of emotion it gives off with such simple sounds. It expresses the sadness, happiness, hatred, and jealousy of Lucy as well as the other characters.
It probably is the most emotional song I've heard in anime.
Even though it is not an actual anime, I still think it fits the category. So it HAS to be said. I vote for Shiroi Kisetsu (White Season) from Kana Little Sister visual novel as the most emotional song in the known universe forever and always.
Ah!!! I have something that seriously made me tear up TT~TT (i don't usually tear up for animes) :)) Ummm have you watched cross game yet? :) There's this song they used for bgm when the sister of the main character died, it's called "Koikogarete Mita Yume 恋焦がれて見た夢" by Ayaka, it's really touching :') You should listen to it sometime ^_^
EcchiEcho said: So here's how I came up with this topic. After I watch an anime I always get like all the music from it. Today I just finished Clannad After Story. Oh yes I am going to vote for a Clannad song. Many of them were good but I must say the most emotional song from what i think is one of the most emotional anime's has got to be "The Place Where Dreams Come True 2." The full version. Probably the second most emotional songs were the Angel Beats songs especially the ending