These for letters stand for "Fellow of the Higher Education Academy".
Did you ever attend a lecture and think "That person should not be allowed to teach"? Or, rather, "somebody should teach that person how to teach"?
In Britain, that is a thing: if you want to teach at a university, you are expected to get a teaching qualification. My university considered it so important that they mentioned it at every step of the hiring process (fair enough).
So they sent me through a special course, the Postgraduate Certificate in Academic Practice (PGCAP). This is taught at the level of a postgraduate master, but has only about a third of the credits. So, I basically have a third of a master in teaching for higher education.
I learned about many intriguing concepts (like flipping classrooms, following the UK Professional Standards Framework for higher education practitioners, and using Bloom's taxonomy), but the most tangible benefit was that I was allowed to keep my job. And that alone is already a big advantage.
From a business card point of view, I really like that I now have a postfix degree (my other degrees are from Germany and are put in front of the name). Not that it matters, but it is kind of neat.