Thought that song always had a FFIX vibe to it. I actually remembered that song as soon as it started playing, really good song.
One of the things I like about anime is that you can come across some great OSTs. Having a great OP/ED helps, but I love it when a show has a fantastic selection of BGM. For example, SSY had a very, very short OST, but easily 90% of the music from that show was stellar. There are songs I hear that will still illicit an emotional response from me. Some that stuck with me:
Nagi no Asukara had a great OST altogether, but this song was my favorite:
Shigatsu/Your Lie in April had some really good music on its OST, which I think was overshadowed by the importance placed on the performance pieces. This song still gets me a bit choked up, especially when I think about when the piano solo version was played:
One of Tamako Market's strong points, imo, was its OST. I couldn't find a yt version, but someone had it on their SoundCloud, but the track "Houkago (After School)" and its piano solo version always came in at the perfect moment. Also that OP/ED combo was really good.
This one from Nisemonogatari.
And, of course, any veteran of Shinsekai Yori can attest to how perfect this song fit into that show. Always used at just the right time.
When it played during episode 3 of Euphonium, I almost cried.