Love the suggestion of Stevie Ray Vaughan on Austin City Limits. Different kind of powerful than most of what is being discussed here, but as effective as any.

As regards movies, lots of great ones have been mentioned. Anyone out there seen a foreign film called The Tin Drum? It's guaranteed to depress and disturb. Not sure why that came to mind, but nobody else had mentioned it, so....

I know it's off topic, but a 3-minute song can also be extremely moving. I heard a song recently for the first time that had me just about ready to jump off a bridge. (I opted to go home and hug my kids instead.) It's an old song by Ernest Tubb called "Our Baby's Book." It tells the story of how he lost a 7-week old baby boy at some point in his life. The topic is hard enough to take, especially for anyone who has or has had kids, but you can literally feel the pain in his voice.