Do you know the name of the boat? What about some wine glasses etched with the name of the boat on them, and then a couple of bottles of wine? I did a search and found this link, for starters:

etched stemware

For those who need or want nothing, always buy consumables. Your basket of gourmet items sounds perfect to me.
Dee

I would do consumables too and definitely something for the kids- preferably something unique from an upscale kids store.
Books are fine but maybe a talking book? Or a cool new game.

We have a similar situation with friends with whom we spend time at their vacation spot. I always take a picnic basket (first year the basket was part of the gift). They don't want or need a thing, and they hate wasted money just to be presented with a "hostess gift" in light of the fact that we are very close friends.

Now when we go, I fill our huge picnic basket with all kinds of breakfast items, as that meal is catch as catch can. Very informal meal, they have help with lunch and dinner only. I take plenty of local fresh fruit, homemade or good bakery assorted muffins, bagel. A few gallons of freshly squeezed OJ from the farmstand, gourmet jams, whatever looks good. In the event there will be children visiting, I may bring some extra things of the picky eater variety. Since we have all been there with the picky eater thing, it doesn't hurt to bring a box of delish donuts that no child would deny. This way, breakfast isn't an issue for our hosts.

Enjoy your visit!

I've always liked to give Edible Arrangements. They're fun (especially for the kids). You could probably have one delivered from a local branch.

Here is a link that might be useful: Edible Arrangements

I like Work's idea. You can do a nice basket and you can even do it in a theme if you wanted - like a breakfast basket, a sweets basket, snacks basket, etc. I've seen nice entertainment themed gift baskets - included movies or rental gift cards, books, popcorn, etc., you get my drift.

Your idea for the kids is a good one too. It would be nice to give them a little something of their own.

As a former boat owner (certainly not a yacht with staterooms!) I would much prefer to have something that didn't need to be stored. Books for the grandkids are great since they can go when the GC leave. Wine is a great idea but would have trouble transporting it to the houseboat? Where is the boat docked - would you be able to stop in the town where the boat is docked to purchase it before boarding? And I like the picnic basket too.

I love, love, love all of your great ideas and the suggestions of things to include in a gourmet gift basket! I woke up this morning with such a lousy headache, fretting about this. Now, though, I feel like this huge weight has been lifted from my shoulders . . . and head ;^D Thank you so much!!!!!
Per all of your suggestions/support, I think I'm going to go with a gourmet gift basket that I put together myself. I'll hit up Williams-Sonoma, Trader Joes and the French bakery for some consumables (thanks Dee!) that are fun and yummy for everybody. Work in Progress, great ideas and I love the one about putting it all in a giftable picnic basket!! I'll also get each of the boys a book, as I LOVE buying kids books. Maybe a fun, age-appropriate book on bugs with little magnifying glasses or something similar. My DS had one like that when he was that age and loved it.
I also like Les' idea of etched glasses with the boat's name on them. Perhaps after we get back home, I can check into finding a place to do it with high-quality, unbreakable barware. I never would have thought of that idea, Les . . . thanks!
Again, thank you for all the great ideas, as I can now stop fretting, knowing our gifts will be special, practical and fun!
Lynn

lynne- Consumer Reports just rated brownie mixes and Trader Joe's was tops along with Ina Garten's - but a big difference in price. Joe's was only $3 while Ina's was $10. The report said that they had real semi-sweet chocolate morsels and used butter rather than oil.

if you know that they are game players(and if you and hub are too), games such as stone age and puerto rico, etc are very good and maybe they are games your friends are less likely to have... go to amazon to find those and other like games!

i would think they probably have plenty of glasses, but i love the paper coaster idea...you could order some of those with their or the boat's name and that's something they could always use!

Lynn, how about some authentic New Mexican goodiess to mix in the basket? I imagine you make a killer salsa.

I like the idea of the books for the GKs. I love to give the gift of books, and am known for either books or B&N GC for all occasion gifts. lol

We purchased books for my nephew about sharks and some other animal (can't remember which animal the other was) that had small scale see-through 3D model of the featured animal in the book. When you turned the pages, it pictured different significant organs, etc. and cool facts about why each animal had differing skin and the like, as well as a child's level explanation of the part each animal played in the wild. Very cool books, but I cannot for the life of me remember where I found them. I am thinking it was NOT a book store, but someplace like Sam's club. My nephew loved those books and found taking the model apart and learning about marine life.

My FIL has always had a boat (yacht), and we've spent loads of time seeing many out of the way places. At times it is hard to keep kids of a certain age occupied while at sea. These books were unlike anything I've ever seen and I spend alot of time in book stores.

Any event, your post about the kids made me think about these books I found for my young nephew, but it has been at least 5 years now. I've done a google search and have come up empty. They make a great gift for children who are interested in animals. If I can find the name of the books or publisher, I will post since they would make great gifts for any child.

consumables & books for the kids is perfect. I would only add that if they are beer drinkers, include in your gift basket a few bottles of interesting (local?) beers --

Love the suggestions.
Our son's girlfriend gave us a big canvas bag for Christmas with the name of our very small boat embroidered on the front. Do yachts even have names, lol??? Anyway, we love and use the bag daily, such a thoughtful gift!
ENJOY your trip!

Thanks again for all the great suggestions. Many of them will be good for future (non-boat) thank you or hostess gifts, as well!
Yesteray while I was in town, I ran by Hobby Lobby and found several great baskets that would work for holding the gourmet foods and wine. I'm hoping that they'll have a 40% off coupon (or a half-off sale on baskets) listed in this weekend's ad for me to use. I also got some great ideas for foods while at Trader Joes and then ran by a local bookstore and found a cute book for each of the boys.
Lynn