All the obvious ones of course:
Watermaker and
solar for independence; coffee grinder and a good french press; big
movie drive;
washing machine;
wifi booster/stealer.... but these things are also just
equipment. Things that make it feel like home for us are the cats (we have 3), a couple of original paintings by a friend of ours of our
current city of Florence (which will be nice when we split in a year for more distant shores). Oh, and of course PROSECCO. That's tough to find outside of
Italy, at least the good stuff (which is also the cheapest)
But in terms of the most useful thing on board that isn't
equipment... I traveled a lot overland in my past life, and was taught to cook in every country I spent time in, which happens to include almost all of
Asia, from Qatar over to
Vietnam,
Indonesia up to Siberia and everything in between....Most important thing, hands down, what I wouldn't sail without: SPICES.
A
bilge full of spices, masalas, curry mixes, sauces, pastes, oils, ghee, tahini, miso, dried shrimp, tins of canned bean shoots and bamboo and chilies and coconut milk.... They last forever, you don't need much, are
cheap if you find the right store to stock up, and can make the most hasty and frugal meal of rice or beans or lentils or chickpeas (another little
bilge full) taste like manna from heaven. So yeah.... SPICES!! They also make the
boat smell amazing... like a marakesh trader sweating cumin in a chinese granny's
galley married to the queen of
thailand coming out of an indian
food coma sailing their junk brimming with Kampot pepper to Hanoi

THAT'S my jam right there, ladies and gentlemen. I just made myself hungry typing it....
I do like the paintings tho. And the little black kitty in the corner is all right too