This is especially true when I'm alone; I am one of those people you see in their car, totally rocking out to a song and possibly making you question the safety of being next to me (don't worry, I have plenty of practice singing/dancing while driving). However, I have come to the realization that I am probably absolutely hilarious to watch, as I definitely get into it when I know the words, and have gotten my fair share of strange looks. A few days back I noticed the passenger in the car next to me started to imitate me; needless to say I pulled around next to them and just started him down at a red light to make him feel uncomfortable (totally worked). However, I really have no problem with people seeing me; I am doing it in an untinted car after all. I tend to do the same thing when alone and just listening to music; at the very least I will mouth the words, and I have been known to rock out with air guitar and pull off some wicked dance moves you will be lucky to never see. I tend to be more reserved about these aspects when I'm with others, less out of embarrassment and more due to it being distracting from either the music or the conversation at hand. I also am fortunate to be well aware of my actual lack of singing or dancing talent, and so embrace the cheesiness I probably give off when I really get into a groove. C'est la vie.
Music is awesome, and intrinsic part of my life, and something I truly cannot see myself every without. There are so many genres, styles, and so on that there will always be something new and interesting right on the horizon. I'm fortunate to not be terribly picky either, which means more often than not I will be okay with a song, even if it isn't one that I would listen to all the time. Despite this I tend to get in ruts of CD's or bands that I really love, and will sometimes listen to essentially the same songs for a month or more (Motion City Soundtrack's newest CD didn't leave my car CD player for a good three months).
I guess what I'm trying to say is music is good, and I enjoy it.