Ask HN: What are some problems solved in unrelated domains?

Elaborating, what are some problems that were being experienced by one industry or domain but were solved elsewhere and were adopted by the industry plagued by the problem? Even better if the answer was really obvious for the people who solved it or solving it involved cross-domain knowledge.

For context, I recently heard having a breadth of knowledge (along with depth in chosen areas) is really helpful in problem solving and I'm looking for concrete examples for the same.