The New Penguin Dictionary of Modern Quotations

This book replaces completeness with something better-- quality. Keyword and thematic indexes. A couple of sentences giving background for each person and, if necessary, the circumstances of the quote. This is the thing to pick up if you're interested in quotes that are a little hipper than Barlett's I've-heard-that-a-million-times quotes. Great fun to browse, e.g.: "I think it pisses God off it you walk by the color purple in a field somewhere and don't notice it"--Alice Walker