One of the more enigmatic blessings we hear on Sukkot is "May G-d merit us to sit in a Sukkah made from the skin of the Leviathan."
Many people let modern Hebrew get the better of them and mistake Leviathan for "Whale". Happily fans of Greenpeace need not worry. Leviathan in biblical Hebrew would appear to be some kind of sea monster (see the whole of chapter 41 in Job).
Surfing the internet I did find this lovely picture of a Leviathan themed Sukkah on SukkahCity:
And for those of you still thinking of a Whale skin Sukka I was also reminded of this infamous video of the exploding whale: