When I'm down I seem to draw comfort from tragic or melancholy music. Some of the music of Beethoven, Brahms, Shostakovich,and Billie Holiday fill the bill then.
When I'm already in a great mood, some of the music of Beethoven, Mozart, Saint-Saens, or Ravel can help me celebrate, as can some rock, klezmer, tango, or Latin jazz.
Someone mentioned "Melissa" by the Allman Brothers. I like this song but I always become very sad and almost tearful, for a few minutes, whenever I hear it. "I Want You Back" by the Jackson Five has the opposite effect. Whatever mood I am in, hearing this song will make me fell like I've just had a double espresso and a shot of tequila, at least for the few minutes that it's playing.
