Cory Doctorow's novel Down and Out in the Magic Kingdom, "whuffie" is the ephemeral, reputation-based currency. The book describes a post-scarcity economy: All the necessities (and most of the luxuries) of life are free. Whuffie has replaced money, providing a motivation for people to do useful and creative things. A person's Whuffie is a general measurement of his or her overall reputation and is gained (or lost) according to a person's favorable (or unfavorable) actions.

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