Music can be so incredibly powerful in conveying and spreading emotion to its audience. It's sometimes the only way to get the message across, and can - by itself - succeed in spreading happiness, romance, sorrow, etc. It's sucha pleasure to have a good song play and let your minds wander to relate that music to things, or even to just let it consume you.
I ALWAYS have my computer/iPod playing playlists when I'm driving, doing my hw, on a plane, etc. It helps make the day go by better!
Plus, when I'm drawing or writing, playing music helps improve what I'm doing because I'm not just fabricating or pretending to feel the emotions. I actually AM, and can therefore express that emotion even better!