I'd like something that'd provide discounts for travel -- several people mentioned the airport, and that sounds okay. If I lived in the right places, I'd be interested in some kind of part-time job with the cruise lines, but I don't live in the right places.
My husband and I've talked about seasonal work at state or national parks. We started talking about this when we took a WONDERFUL tour with a fellow who must've been in his upper 80s in a state park out west. It was just our family on the tour, and we loved every minute. He was full of stories about the park, the wildlife, etc. At one point we drove past a group of RVs, and he commented that he lives there during the summer . . . but during the winter he goes back to his home in Texas. We asked him about it, and he said that people come back year after year, and they look forward to spending time with their "summer friends". In spite of his age, he was no one with whom to trifle: At another point in our tour we came upon a church youth group who was doing something VERY unsafe. He excused himself and left us in the Jeep, and he got out at STOPPED that mess. Then he radioed in to park security. Yes, we admired the old guy and even have a picture of him on our wall in one of those collage frames.
Similarly, some parks hire people -- mostly retired people -- as monthly hosts. You camp for free for a month, and in exchange you "make the rounds" and collect the $12 fee from each campsite around dinnertime, are available for emergencies and information.
Similarly, I could see working at the ballpark as seasonal work, but I wouldn't want to cook -- that's too labor intensive for me. I'd take tickets or parking lot money.
Or at a museum during busy seasons.
A couple years ago we went to hear a famous author speak at a nearby auditorium, and we noticed that most of the ushers were senior citizens. We asked and learned that this is a volunteer job. We agreed that we'd be VERY interested in volunteering so that we could hear the speakers and concerts and see the plays for free.
To use my current skills, I could work as a private college counselor, helping families navigate the process of SAT, college admissions, and so forth. I do that for free now.
And I'm investigating becoming an SAT administrator. That's only something like 6 Saturdays a year work, so it wouldn't be much money or very intrusive to my life.