Back to the Future seems to be fiction, as Doc Mui built himself a DeLorean, and he and Marty Rose ape the movie, but I don't recall Dr. Emmett Brown or Marty McFly ever appearing. Or did I miss it?

And both the Honorverse and Vorkosigan references were all Redneck's doing, so unless one of the other Eryie people loves those universes like he does, I doubt we'll see any more of them; a long-ago post by Gryphon said, at the time, that he hadn't read them.