Hard to describe how useful this book is. Tell people about it, and they're likely to say, 'Oh, you mean a thesaurus,' and you say, 'No, not exactly,' and then they say, 'Oh, a reverse dictionary?' and you say, 'No. Better.' It's for those times when you sort of know what you're trying to say, but you either can't think of the word or you've used a word too much and you need to jiggle loose from your cranium some new ways of trying to say it. And it leads you on and on down an ever branching set of references so pretty soon you find yourself just sitting down and reading the Flip Dictionary instead of writing. It's that much fun.
An invaluable resource, recommended to me by a fellow writer.