I don’t know a whole lot about classical music, but I do know that the Benedictus from Beethoven’s Missa Solemnis is one of the most beautiful pieces I’ve ever heard. I was just listening to my iTunes on shuffle, and when the Benedictus came on I stopped what I was doing and just listened. It consistently brings tears to my eyes. Anyway, if you haven’t heard it, do yourself a favour and listen to it, and then listen to it in the context of the entire Mass, where it’s even better.