I've recently read about an inflatable ferry from a Slovenian company. When folded, it's portable, easily inflatable, and can carry up to 5,000kg, which is a heck of a big vehicle!
The company also says their boat is "practically unsinkable and incapable of overturning", which I think was also said about the Titanic. Of course, there aren't any icebergs in the archipelago, so it should be safe.
I certainly wouldn't have use for such a vessel, but it might be handy for some ad hoc construction projects around the islands.