At the Port of Pensacola, we happened upon a behemoth, the Global 1200. It is a 532 foot long service and construction ship for deepwater derricks. B pointed out the helicopter pad on top. The website states that it can provide living quarters for 264 people, has a gymnasium, a full movie theater, satellite TV and an internet cafe.
This link shows a picture of this ship with its enormous cranes extended.
The ship's flag is from Vanuatu. (I had to Google that!) That is a collection of islands in the South Pacific between Australia and Fiji. I learned that it was the location for a Survivor show. The ship has been in port since September and is due to leave in mid-December. I would love to see the port bill for fees. For a start, I understand that dockage is determined per foot length of the ship.
A second large ship was not quite so visible. It is the Boa Olympic of Norway and is in a similar business. It also has a helicopter pad. This ship was just over half the size of the Global 1200.