Of the literally thousands of mods I've seen for Skyrim over months, this is probably my new favourite, by virtue of the fact it adds giant monsters, turning the game into a very Nordic Shadow of the Colossus.
Each mythical beast has its own lair - a location on the map you can fast travel to - and each is enormous. There are giant crabs, giant fish, giant ice beasts and...giant horkers. As you can see above.
There are quests, salty old sea captains who whisper about the giants of the deep...it's the kind of thing that should have been an amazing expansion, but is now even better, because it's free.