Finally a subject I know about!
Here is a photo of my 7yr old greyhound enjoying the sailboat. At first I thought she would hate it, but all she loves it for the firsts few hours, then she keeps walking towards the open transom... I think this is a sign that she wants off. It's only when we have to keep tacking that she doesn't enjoy it.
We keep our boat on a moring... she seems to like the dinghy ride to the boat best!