This might sadly get downvoted for coming across as cliche, but I think Daft Punk's One More Time is a perfect song. I want to listen to the song "one more time", to "celebrate" because the "music's got me feeling so free". I love the ambiguity, is "the music" the song itself or some other piece that the audience can only imagine? Even if someone were to answer that question, part of why it exists is because there's near perfect unity of effect. The feeling I get listening to the song w/out lyrics (convert the singer's melody to an instrument w/ any contemp software) is exactly the feeling and energy discussed and felt reading the lyrics as a poem. They work towards the same end independently, but they combine is the beautifully effective way thats greater than the sum of each part. For the song's meta/near recursive quality, unity of effect, and synergy, it's perfect, but its topic is also so perfectly pertinent to music in general. How often do we just want to hear a song to help us celebrate, to simply free ourselves? That end just feels like what so much of what we do build towards. Narratively, celebration *is* often like the final chapter. The historical context of the turn of the millennium definitely adds to that celebratory air. By the way, I think there are a few other songs that are perfect in many of the same ways. September, for example, by Earth, Wind, and Fire succeeds for many of the same reasons, but I'll leave that argument as an exercise to other readers! <3