I work in a public-facing job (or at least I used to before COVID-19) and am very good at customer service and handling difficult customers. If someone is really angry or abusive I get flustered like anyone else, but I am very good at diffusing most people before they get to that point, and I have often enjoyed the challenge of creating a positive outcome out of a negative customer interaction (although after more than a decade in customer service roles, I'll admit I don't get the same joy out of it that I used to!)

I also know a lot of fiddly grammar and style rules, like how to use a comma correctly or the difference between "which" and "that." I am not actually a prescriptivist when it comes to grammar, but it's still handy knowledge.