this is a horrible picture, but it has not been disproven. supposedly, back in the 1800s, an octopus that was over 80 to 100 feet from tentacle tip to tip washed up dead on a shore. it took a team of horses to drag it up on the beach, whihc mostly destroyed it (Molluscs are pretty fragile, having no bones., especially when dead)
supposedly a college in england (Oxford i think) has a chunk of it in formadehyde, and the striations of the tissue are fairly consistent with an octopus. it is considered inconclusive, and not enough evidence exists to prove or disprove the claim, but it invites the possibility that three are some MASSIVE creatures living in the ocean. :D