This. Universities are full of interesting departments teaching all kinds of fascinating subjects. I really regret not taking more advantage of this fact when I was at University. Don't be scared to leave your department and see what else is on offer. Who knows you might just stumble on an idea in some unexpected corner of academia that will turn out to be more influential to your future than any CS course you take. See for example the story about Steve Jobs taking a calligraphy class while at school.