I think music is a great form of communication, and I think that's one of the reasons why I love video game and film music so much. Communication is about context; music set to epic events like video games makes such a difference in the message to me. And it can act as communication all on its own, even without lyrics. I think that's amazing.
It also seems to be this strange cosmic constant between cultures, and something that defies explanation - though you can break down the music mathematically, it's just never a good enough explanation of what music is, and why it does what it does.