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Prolog is very succinct and interactive so it is quite nice for modeling and analysing problem spaces, similar to what you might do with Z3 or some other solver library.

Prolog also has exceptionally good string management through DCG:s. If you have a bunch of structured text and want to query it, Prolog allows you to do that. The syntax is very simple so you can even just sed your data into Prolog code and load that sometimes.

Supposedly SICSTUS Prolog is used in flight booking, and NASA did something with it sometime, but that's kind of obscure. If you ever need a rule engine, consider poking it with logic programming for a bit, perhaps it'll turn out both pragmatic and elegant.