"The Dead Mountaineer's Hotel," by Arkady and Boris Strugatsky. This is a novel they wrote just prior to "Roadside Picnic," the inspiration for the S.T.A.L.K.E.R. movie and video games. Very funny at times... sort of a mashup of Agatha Christie murder mystery with a sci-fi/fantasy edge.
After I finished it, I was inspired to re-read Roadside Picnic, which I haven't done in a while. That's a classic, with a very different feel from Western sci-fi. I might try to track down some of their other books that have been translated.