I like to listen to "Chiptunes", music that uses the sounds from old 8-bit video game systems and the like. I like to imagine that every action I take in life earns me points, and that I have infinite lives. And its nice to have an 8-bit soundtrack to that.
Helpful hint. You can tell the difference between NPC characters and non NPC characters (I know it's redundant) by whether they're repetitious. If someone repeats the same thing over and over again, its okay to hit them with your whip or knife or baseball bat, because they're computer generated.
here's a few chiptunes I think you'll enjoy.