The Dead Man’s Brother, Zelazny. Yes. The manuscript for Dead Man’s Brother was discovered by Zelazny’s agent, presumably recently, certainly after Zelazny’s 1995 death. I found it interesting to read a work that is clearly Zelazny, but is not predominately sf (though it certainly bears a distinct trace of sf). It’s a bit preachier than RZ usually was, and I’m not sure a crime fiction devotee would be entirely satisfied, but I was.
I found the publisher’s mission statement charmingly nostalgic:

Hard Case Crime brings you the best in hard-boiled crime fiction, from lost pulp classics to new work by today’s most powerful writers, all in handsome and affordable paperback editions. The yellow ribbon represents your assurance of quality.

Update: Many thanks to Tom Jackson (see the comments) for pointing me to an account of the history of The Dead Man’s Brother.