Space/Science
"For Us, the Living" was written by Heinlein about 1938-9, before he wrote his first sf short, "Lifeline." The novel, "For Us, the Living," was deemed unpublishable, mainly for the racy content. So racy is/was the content that in the 1930s the book could not even have been legally shipped through the US mail! For this reason, after a few publisher rejections, the novel was tabled by Heinlein, but the content was mined for his later stories and novels. A fellow named Nehemiah Scudder even appears in "For Us, the Living." It's important to point out that according to those favored few who have thus far read this long lost Heinlein novel, it did not go unpublished because it was bad--they say it's quite good, though clearly a first novel by the author (it has a two and a half page footnote!). It was unpublished because the mores and culture of the time would not allow it. "For Us, the Living," was put aside, and eventually lost. The Heinleins apparently destroyed all copies they had. And because at the time it was written Heinlein was not a member of the science fiction community, no other sf writers knew about it. He had let one or two friends read it, and it is by a long trail through one of them that this rarest of treasures was located.