One Big Ass Ship

How big is the MV Blue Marlin, a semi-submersible heavy lift ship? Why, it's big enough to transport drilling rigs and even other big ships on its deck.
In the 2000 photo above, the Blue Marlin was hired to move the destroyer USS Cole back to the United States after the warship was damaged by Al-Qaeda bomb in Yemen.

Well, carrying one ship is impressive - but what about carrying 18 ships? Here the Blue Marlin transported 18 riverboats and a few large pontoons from China to the Netherlands.
A ship that carries a ship (or ships)? Now that's a big ass ship, but the Blue Marlin is actually not the biggest heavy lift ship in the world. That title belongs to Dockwise Vanguard (the company also owns the Blue Marlin), which has 70% larger deck-size than the Blue Marlin.
More about the Blue Marlin over at Wikipedia and Dark Roasted Blend