Heh, best argument against creationism yet: If God were omnipotent and omniscient and God designed the human body, then it wouldn't be such a phenomenal mess!
Or maybe the Universe was a hastily done outsourcing job?
Seriously though, as messy as organ systems and biochemistry may be, the weird thing is that it all works by itself, using basic chemical properties. I remember how some textbooks can make it sound like proteins and molecules are ordered around in a cell, but in reality everything just floats around, is attracted and repelled to other stuff in the right places, and it works.