According to this study, reported last November to the American Society for Neuroscience, prolonged exposure to the Beethoven piano sonatas has a quantifiably positive effect on people with depression. I've heard the same thing regarding Gregorian chants, the sonorous tones of which are augmented by the acoustics cathedrals. The musical intonation, as well as liturgical repetition, facilitates the transfer of one's mind into a contemplative state. But that seems to have been replaced by entertainment-of-the-day praise music at some churches. But anyway, start listening to those sonatas.
I recently heard a podcast on Radiolab out of NYC that did an episode on an artist in San Francisco who took Beethoven's 9th and stretched it out over 24 hours. By stretched out, I don't mean he played a 24 hour version I mean he took, say, a 5 second note and electronically altered it to last 3 or 4 minutes. It sounded kind of cool; however, there's no way I could sit through it for more than an hour. Not sure if this has relevance to your topic. I just thought it was interesting.
