The Bahama's mail boats are the lifeline to the Out Islands and are precisely what you're picturing; slow, no-frills cargo ships that deliver food, necessities (and sometimes passengers) to the remotest of communities. And are one heck of an adventure if you can score a spot. 

Passengers are a bit of an afterthought here, and unlike other boat journey's they require a reckless sense of adventure to even secure a ticket! If you're imagining posting in a local Facebook group à la Greg you're on the right track. Study this guide like your life depends on it, if you're serious about setting sail. 

Here's an example of routes departing from Nassau:

Great Exuma

Population: 6,500

Highlights: The busiest of the islands — your last stop before paradise.

Boat: MV Captain C

Cat Island

Population: 1,500

Highlights: Pink sand beaches, and a hilltop hermitage.

Boat: MV Legacy

Andros

Population: 7,500 (west side has fewer than 500)

Highlights: Wild blue holes and the 3rd-largest barrier reef all to yourself. 

Boat: MV Bahamas Daybreak

Crooked Islands & Acklins

Population: 300-500

Highlights: Loyalist ruins, lighthouse and empty beaches. 

Boat: MV United Star

Ragged Islands

Population: 50-70

Highlights: A near deserted outpost with endless solitude.

Boat: MV United Star 

Pro tip: Got time on your side? Pick an island where the mail boat comes once a month — you'll have it mostly to yourself. And once you're back on land, send us a postcard please :-)