I have a small amount of professional experience with Scheme and programming language design & implementation which I put on my resume. I've found people bringing it up is a pretty good bellwether for interesting interviews and people who are good to work with. Has it gotten me in the door ever? I don't know. Go ahead and do it.
My experience has been about the same. I don't think it got me any interviews/jobs but it hasn't hurt me to put it on my CV. It simply gives the interviewer something to guage where you are coming from in terms of style and knowledge of computing.
There’s a fairly slim chance having them will help you with job applications to most companies. But they’re vanishingly unlikely to hurt your chances anywhere.
Just don’t put anything on your resume that youdon’t know well enough to discuss in depth in an interview and start deciphering legacy code in your first day on the job.
I usually only put technologies I have used for work I was paid for, or at least was reasonably public.
I.e. I learned haskell at college, but I never put it in my CV. I have clojure in there, because I actually worked on a small clojure project (while doing QA at RedHat). I did put C++ on my CV, even though I only used it when writing my thesis, because I considered the project large enough. And I did put a sys-admin on there, despite the fact that the work I did with my friends to maintain a community server (I think we had like a forum and a church website there?) was not paid.
In general, I am trying to avoid blank statements like listing an alphabet soup of technologies, and just list various projects I have been part of, scope of my involvement and the technologies I used there. I am not sure if this helps me (mostly been hired through friends), but when I was on the other side, reviewing resumes, I really liked the project-based approach, rather than a list like {java: expert, python: intermediate, haskell: beginner} :D
I would ask you questions about Haskell and functional programming, if you get them right it will definitely be a plus, but if you say you know Haskell and can't write basic monads from scratch you are doomed
