We are going to Mexico for my parents 25th wedding anniversary, what should I get them as a gift?

My parents are the people who literally have anything. We are going as a family (extended as well) to Mexico so they can renew their vows on the beach, because Mexico is their favorite place to be. What should my brothers and I get them? (money is no object) We have prepared the good ole' slideshow to show at dinner that night and have the speech that will bring the room to tears.... but other than that we are stuck! Please help!