We bring the big 64oz QT cups (cleaned) with spare lids and straws in our checked luggage. (QT = QuickTrip - a local gas station chain like Racetrac, etc). Use the paper cups to refill. We leave the cups for recycle at the end of the cruise so as to not take up space for the trip home in the luggage. You can brew hot tea in the coffee cups by the serving stations (takes 2X - 3X's), then you pour the hot tea over ice in your QT cups. Makes an excellent substitution for brewed iced tea. My DW and I drink a lot of iced tea. You can also use them on-board with soft-serve ice cream to make Coke floats or root beer floats to enjoy around the pools. I've not heard about the "cherry" Cokes at dinner, but we may have to try that the next time.