Craig Newmark

Craigslist began in 1995 as Newmark's email list of events in San Francisco and became the place Americans sold their sofas, bikes and cars to each other. The model is unusually lean: most listings are free, money comes from fees on job ads and a few other categories, and the site has barely changed its plain design. It shows that a reuse marketplace does not need slick software, only enough local buyers and sellers in one place.