It might seem like a great joke at the time, putting a live octopus on your husband's back, but these cephalopods are no laughing matter. Ask any fisherman who accidentally winds up with one in their nets - those suckers stick like superglue. Not only that, but octopuses actually have well-developed venom glands, and in distress they won't think twice about stinging you.
Take the blue-ringed octopus, for example. This little guy with the striking pattern, found in Australia and parts of the Pacific Ocean, contains enough venom to kill 26 adult men within minutes. First your whole body's paralyzed, then your lungs stop. Then you're dead. The man in this photo didn't encounter one of those, thank god, but he did cop enough to be put in hospital.