Ultimately, any threat to hermit crabs could also endanger their ecosystem, since the scavengers play several key ecological roles.

FORBES: Can 3-D Printing Save Homeless Crabs?

Organizers hope this diversity of ideas will produce a style that hermit crabs like, and eventually lots of different ones.

FORBES: Can 3-D Printing Save Homeless Crabs?

MakerBot Industries, a 3-D printer company in New York, wants help designing and producing plastic shells to fight homelessness among hermit crabs.

FORBES: Can 3-D Printing Save Homeless Crabs?

While plastic shells are already sold commercially for pet hermit crabs, Project Shellter adds a twist by letting people worldwide design their own.

FORBES: Can 3-D Printing Save Homeless Crabs?

In a pinch, wild hermit crabs will take whatever they can get, says Rafael Lemaitre, a research zoologist at the Smithsonian Institution.

FORBES: Can 3-D Printing Save Homeless Crabs?

Hermit crabs are all over the atypical black sand beaches, where the sand is so dark it exudes an ominous and divinely desolate quality.

FORBES: Take A Trip To The "Happiest Country On Earth"

Back on shore, the two-room Maria Mitchell Aquarium might be overlooked unless your kids are excited to see local fish and touch hermit crabs.

BBC: The kid-friendly perfection of Nantucket

These hermit crabs strike fear into the hearts of seated airline passengers whenever they board, because their shells invariably bang into innocent shins all the way to their seat.

ECONOMIST: Nomads at last

"Seahorses can be a little tricky and hermit crabs are always something of a 'guesstimate' as it's difficult to tell which shells are inhabited and which are vacant, " she added.

BBC: Newquay's Blue Reef Aquarium stock take is under way

Around the turn of the century, as some astronauts, typically executive road warriors, got smarter about packing light, says Mr Saffo, they graduated to an intermediate stage, becoming hermit crabs.

ECONOMIST: Nomads at last