It's almost embarrassing how much your dog knows about you from just a single inhale. Their sense of smell is at least ten THOUSAND times more acute than ours, which is why they can sniff out bombs and drugs and even the beginnings of melanoma growing on your skin. (Of course that makes their need to coat themselves with dead seagull at the beach all the more baffling.)

Still, it's a fascinating topic that'll be in the news for a bit thanks to Alexandra Horowitz's latest book, "Being a Dog", which is all about the miracles and mysteries of the canine nose. She did a great interview on Fresh Air that'll destroy forever any illusions you may have that you've managed to sneak a cookie in the kitchen with your dog none the wiser.