Whuffie

Whuffie is the ephemeral, reputation-based currency of Cory Doctorow's science fiction novel Down and Out in the Magic Kingdom and his short story Truncat. This book describes a post-scarcity economy: All the necessities (and most of the luxuries) of life are free for the taking. A person's current Whuffie is instantly viewable to anyone, as everybody has a brain-implant giving them an interface with the Net.