We put some decorations on our door on our last cruise. One night we came back and they were on the room next door! Our room steward was standing there and when we asked if he'd done it he said "Oh, no
!, with a smile. I'm sure he would have moved them back before he left.
I bought the magnetic paper and some ship themed decorations (I found mine at Office Depot) that are usually used for scrap booking, glued them onto the paper and cut them out. Besides being fun, they
are good for finding your cabin!