Anyone that has seen Eva has probably heard this, it hasn't been mentioned yet in this thread, so I thought I'd give it a plug.
Thee Silver Mt. Zion Memorial Orchestra - 13 Angels Standing Guard 'Round the Side of Your Bed
My "most beautiful" piece of music has turned into a rather long list by this point in the thread. I still stand by my original post though, though this song... something about it is truely otherworldly.