Depends on the time of day and activity!
Right after diving, Nutty Jamaican (rum cream & Frangelico) or Nuts & Berries (The Couples version is Frangelico, blackberry brandy, Amaretto). Both served on ice with a cocktail straw. The sweetness helps balance out the saltwater from diving, and when its your first drink of the day, gotta go pure liquor!
Standard pool bar maintenance drink, Appleton V/X, coconut rum, and pineapple juice with a dark rum floater (followed by shots of Nutty Jamaican or Mexican Dessert)
For walks down the beach to Office of Nature or any other sweaty adventure, Red Stripe, Carib, Miller Lite, or any other readily portable beer.
Cat Cruise, rum punch
Sunset Bar Shuttle (to Pushcart), Guinness
Piano Bar, Guinness or Heineken
Any stop off-resort at a jerk stand or gas station, Dragon Stout
In-room cocktail before dinner, vodka with either cranberry, tonic, ginger ale or Ting. Or, maybe a mimosa or rum & Pepsi (since they don't have Coke!)
So basically, every mood has it's own unique libation. Don't limit yourself to the same ol standard drink that you can always get at home. Mix it up!