OK, I read of your Ship Coins, Pennies made into Collector Ship Pennies, Magnets, etc.... all neat ideas.  Someone, many months ago mentioned the paper border that circles the commode when you first arrive on the ship as mementos that he saves - very unique.  Carnival used to give out large  prints of the ship each time you cruised and I still have those which are so beautiful. I used to hang them on a wall in a hallway.  Now I am in a condo so I do not have the room to hang them.  I have no idea where the multitude of Ship Pins that I have received over the years are but I did find two for the photo below. .  

Here is a photo of my collection that I hastily gathered together.  The only ones that I actually purchased on board a ship are the key rings and the ship models or ornaments.  The rest: coasters, plates, mugs, medallions, magnets, playing cards, stationery & pins, etc I either was given or won. I also have tees, journals, totes and luggage that were too big to fit in the photo.