The unusually mild winter in my area seems to have given us a huge number of fireflies--or, as I prefer to call them, lightning bugs--this summer. It's been a real treat to go out and see them, although I never have been able to distinguish one species from another.
There was, though, the time a British friend saw them for the first time and asked, in terror, why there were little lights all over my yard. He thought he was hallucinating. I took great pleasure in explaining what lightning bugs were. In retrospect I think I explained too quickly, and would have gotten even more pleasure out of letting him think he was losing his mind for a while.