Wonder what sort of venue this would be.
Like this one:
http://en.wikipedia.org/wiki/RMS_Queen_Mary
Photo galleries here:
http://en.wikipedia.org/wiki/RMS_Queen_Mary
I was on the Queen Mary for a afternoon and/evening in 2009 and ran into a group of about 20 people in 1920’s costume doing an Indiana Jones style larp. They said they had an arrangement with the hotel to pay visitor admission and then they pretty much had the run of the visitor areas of the ship, including the ballrooms.
They gave me a card, but I lost it while driving around over there. 
And now I thought I’d do a quick google search to see if I could find them, but found this instead:
Steampunk Convention held there.
Check the events page, there were a number of larps run. 