I have to admit that I am a sucka for TV theme songs.  Sometimes I enjoy the intro more than episode.  I think it is because the intro is a constant and reminds me of all the goodness from every episode I have watched.  Holly bought me season 5 of the Mythbusters for Christmas, and the intro at the beginning of each DVD just puts me in a good mood.  It is not the “theme song”, but in this case it is even better.  Several times I have power-cycled the DVD player, because I missed the intro while I was switching inputs on the TV.  As a bonus the kids love it too (especially when the tribal guy delivers an enthusiastic “BOOMDIYADA!”).  I defy you to be in a bad mood after enjoying this clip.