A commentary on isolation and insecurity, yes, no question -- but look at that dog and what he does and tell me that doesn't put a smile on your face!
And I have to agree with the video for Exhibit 13; it hit me like a ton of bricks the first time I saw/heard it, and I still get a lump in my throat every time I hear it. It's been a while, but I seem to remember that it was also pretty powerful on their live DVD. The falling papers are projected on the entire front wall of the stage, and it seemed much more immediate and involving in their live setting. Check it out sometime.
My "musical gut-wrencher" is Kate Bush's song This Woman's Work (from her A Sensual World album). Especially associated with its video, but even on its own, it brings me to tears every damn time. A strapping, macho guy like me! Disgusting.
cheers,
supervij