We are traveling with another family this year - on different decks - and wondered best way to track each other down on board. What have you all done when traveling with large groups to find each other. Cell phone and text prob won't be an option due to roaming charges. Is this what the wave phones are for in the rooms? What about small walkie talkies like we've used while skiing. Of course we plan on dry erase boards on the doors to leave messages but other ideas that have worked well?