Back when I was a child, I used to haunt an old used book store in my home town. I would literally spend the entire day in there, either reading or talking to the owner. I doubt he got a half dozen customers in an average day, but I loved it there. I told him that I wanted to buy his store, if he ever retired.
Fast forward about 25 years, and I happened to be passing through my old stomping grounds again, so on a whim, I checked to see if the bookstore was still there! It WAS!! And when I walked in, the old familiar smell of the place triggered an olfactory memory that almost overwhelmed me. All the books were still in the same areas as before. It was like walking into a time bubble. New owner, though, who had lived my dream by doing exactly what I wanted to do - he bought the store from the owner and didn't change a thing.
My ideal 'job' is still the dream of sitting in a tiny used book store somewhere, surrounded by thousands of books, reading, uninterrupted for hours, and visiting with the people who wander in, no worries about money or time.
Barring that, I think I would truly enjoy being part of an international emergency response team, helping out wherever catastrophe strikes, making peoples' lives just a little easier in what is probably the bleakest time in their lives.