I was interviewed for an article on reputation economies in the current issue of the Utne Reader — the piece is online now!
In the 2003 science fiction novel Down and Out in the Magic Kingdom, author Cory Doctorow imagines a society where all of life's necessities are free, and market laws such as supply and demand cease to exist for everything else. Instead of trading in a hard currency, citizens living in this "post-scarcity economy" measure their wealth with an ephemeral, reputation-based currency called "Whuffie." Doing something that benefits the community, like baking a cake or writing beautiful poetry, increases a person's Whuffie, while causing a traffic accident or publishing clumsy prose can temporarily put you in a virtual poorhouse. Everyone is wired into the Internet via brain implants and can routinely view and modify others' standing instantly (and free of charge), ultimately making one's status the subject of majority opinion.
(Thanks, Brendan!)