Several years ago I went to a training event in Long Beach, California and was housed aboard the former luxury cruise ship The Queen Mary, now a floating hotel. This "Ghost Ship" has a history of hauntings including phantom swimmers and wet footprints beside a long-drained swimming pool, a ghostly woman who roams the ship, the sounds of screams and scraping metal, and sightings of a man who was once crushed by a watertight door. (We had a couple of odd happenings ourselves while on board.)The Queen Mary is larger than the Titanic. She's so big that when you look down her corridors, you can see the how the deck is curved downward from bow to midship and back up again to the stern. She has several restaurants and bars onboard, and hosts a massive Sunday Brunch in the grand ballroom that I believe is the single largest room ever built inside a ship. There's also an onboard shopping mall, a large museum below decks, and a "Ghost Ship" tour that takes groups to some of the haunted locations and recreates spectral visits with special effects.
http://www.gettysburgghosts.net/queenmary.htm
Every Halloween, The Queen Mary hosts a bash called the Shipwreck Halloween Terror Fest. This year will be the 13th Annual Shipwreck. One of these years, I hope to make it to the party.
http://www.queenmaryshipwreck.com/shipwreck2007.html