As I mentioned a while back, the short story "Murder on the Hockflieger Ost," which is a prequel to The Forever Engine, is available as a free download from the Baen Books site. Here's the link again in case you need it. It's a fun read.
But while I was writing it, I had a little fun of my own. There are three in jokes inserted in the story, all of them plays on words, titles, or character names.
In terms of difficulty, I'd rate one of them, having to do with an artifact, a very easy find. One of them, having to do with a location, somewhat harder but not impossibly so. The last one, having to do with a character's name, is so obscure I'd say it was impossible to get, unless you have a mind prone to making associations as odd as mine is.
So any and all guesses welcome. I'll post the correct answers in four weeks and discuss the various guesses, provided I receive any. No guess is stupid--it just may not have been what I had in mind.
No prizes for correct guesses, except of course the people's ovation and fame forever.