Can you sail? A lot of cruisers go south and hop islands in the winter before going north in the spring. The carribean should be quite active now. Some will look for crew to handle nightwatches on longer voyages. I wouldn't go with a set itinerary as these guys take their time and follow the prevailing winds. Here's a good site about a guy who hitched yatchs and circumnavigated if you want to know how it's done.
A site with more info on boat hitching:
Cruisers in the anchorage talk to each other a lot, so it might pay to rent a paddleboard and ask if they know someone looking for crew.