Ok this has got to be the strangest and nasty looking thing coming out of the ocean. According to news reports, a Taiwanese fisherman apparently caught this bright green worm, what some say is a ribbon worm, while fishing in Penghu, Taiwan. The green worm is huge and has a pink tongue, or proboscis that darts out of its mouth. At any rate the thing looks like a massive moving ball of Slime (For those old enough to remember the Slime that was sold as a toy in a can shaped like a garbage can).
Some ribbon worms, if this is what it is, can grow to 60 meters in length, though most are just 20 centimeters or so. The worms from the phylum Nemertea can be found in the ocean, in freshwater bodies of water while others live on land. At any rate, this must qualify for the strangest creature of the week.
Most ribbon worms are carnivores with some known to eat shellfish such as clams and other crustaceans, while others are scanvegers. The phylum Nemertea has quite a few of these creatures, all looking equally bizarre.