Recently, I have seen several comments about the mood-enhancing effects of music, such as this Posit Science blog post. For me, good music mostly means classical music and opera. The author of "Civilisation",Sir Kenneth Clark, a noted art historian among other things, says in that book, that no one could have predicted the rise of grand opera. I listened to How to Understand and Enjoy Opera by Robert Greenberg but even before that, I found that the arias were quite uplifting and memorable.
I know there is a field of music therapy but I don't know much about the subject. I found over and over that indeed listening to the right music lifts my mood quickly and efficiently. Music therapy or not, listening to what I like does me good. Not long ago, we put nearly all of our CD's on iPods, one for me, one for her and one for the house. Both of our cars have cassette players in them. Inexpensive electronic cassettes fit in the players and connnect to the iPods. A USB cord keeps the iPod charged in the car while it is playing.