The fourth book in Douglas Adams Hitchhikers Guide To The Galaxy trilogy.
If you like tidy endings and warm fuzzy feelings, this is the "last" book in the "trilogy" (so, really, what do you call a five-book series??).
If you prefer the pain of seeing where Adams took it before repenting, then read also "Mostly Harmless." I wish I'd stopped at So Long And Thanks For All The Fish -- Adams died before he could repair the damage from "Mostly Harmless." See editorial remarks in his (sort of) final work, The Salmon Of Doubt.
And then just don't read Mostly Harmless.
And while you're at it, don't think of an elephant.
See original on c2.com 