Packing for a cruise that's nine nights or longer can be a challenge, and overweight luggage can strain backs and/or incur added airline charges. The final perk of all-inclusive cruising, free laundry service, can alleviate some of the burden. Several luxury lines offer a daily valet service with laundry picked up, washed, folded, and delivered, while others have a self-service launderette on each deck.