Academic Hopeful recently asked, "Do most academics, generally, have this whole fantasy career going on in parallel even when they have a job on the go?"
I'm not sure I'm representative, but my own answer is yes, oh yes.
Long ago, I planned to be an archeologist. I got a bit distracted in college, and didn't pursue that. I still have regrets about not staying focused on my early dream. I have a fantasy life in which I did college very, very differently, and graduate school very differently, and am even now working on Project Troia.
When I was in graduate school, my preferred Fantasy Plan B was to be a baker. I liked the idea of doing something I loved and was good at, something both creative and hands-on, with real, tangible results.
In my early years on the tenure-track, continuing grad-school-plan-C, I developed in loving detail my alternate life as a translator. If I didn't get tenure, I thought, I would go and live for a year in France, and a year in Spain, and maybe for awhile in Germany or Switzerland, and then go to translator school, preferably in Monterrey. I imagined where I would live, and the markets I would shop in, the street outside my city apartment, the weekends recharging in the countryside, exploring village life. It was harder to imagine the school and the job at the end of it all, but I liked the fantasy of creating a much cooler, far more glamorous version of myself, who would not mind leaving academia behind, who could feel out-of-place for better reasons than those of exchanging one small town for another.
In the more recent past, I've had to develop another fantasy, since I'm well past the optimal age for polishing languages. My thoughts have centered on libraries; I've read T.E.'s accounts of the various phases of her career with great interest, not least because of certain similarities in our temperaments and overlap in the places we've lived (I loved Hill Town, but I think going there as a graduate student was totally different from going there as a professor: graduate students plan to leave within a few years, whereas professors are pretty well stuck). Her reasons for leaving a reference library position are comprehensible to me; I want to do my own work, not other people's. Though I've thought about doing a library degree and trying to get a position as a Rare Books librarian, I don't want a job like that of LRU's Rare Books person, who has to cover millenia of written words and work with faculty and students in a lot of different fields. I want to disappear into a library and never come out, and I want to stay fairly specialized. So I think maybe manuscript conservation would be the best bet: back to working with objects, as in archeology and baking, doing something technical (as I planned in my college divagations). Of course, even to start that I'd have to take a couple of years of chemistry; it's not something I could just walk into.
In fact, I think I'm well suited to academia, or at least to the version of it I have found/created. I like and respect my students, very few of whom are entitled snowflakes; I love my research and having time in the summers to concentrate on it, and to travel to where the manuscripts are; though I have a long commute, it is possible for me to live in a major metropolitan area, which does matter to me (though I might feel differently if LRU had a major research library). But I imagine there are a lot of people who, after 20 years doing the same thing, like to think about other possibilities. Some of them realize they really want to do the other things. Some of us just like to try on alternate lives.