A Scanner Darkly is an incredibly moving and haunting novel to anyone who's ever struggled with drug addiction. For a nonfiction book probably "Kill Anything That Moves" which is about the horrifying and infuriatting reality of the U.S. war in Vietnam, and "The Hot Zone" by Richard Preston
"This has been a novel about some people who were punished entirely too much for what they did. They wanted to have a good time, but they were like children playing in the street; they could see one after another of them being killed—run over, maimed, destroyed—but they continued to play anyhow. We really all were very happy for a while, sitting around not toiling but just bullshitting and playing, but it was for such a terrible brief time, and then the punishment was beyond belief: even when we could see it, we could not believe it…."