If you want another, I ran across https://news.ycombinator.com/item?id=6492781 last night. A U.S. Marine encounters a serial killer who specializes in killing Marines. Unexpected twist: the author himself posted the story and commented in the thread.

Pretty sure I never saw that submission at the time. I am tempted to add it to the next HN 'highlights' list, but I suppose it's too morbid.