If you're looking for a cool Dark Knight inspired t-shirt, TeeFury has one on sale today.  Designed by artist Lee Crutchley, the shirt is called Heath and it uses the Joker's famous line "Why So Serious" in a clever way.  Like all TeeFury t-shirts, it's $9 dollars and only for sale for 24 hours.  That means at midnight tonight, they stop selling it.  More images after the jump: