If Pandora, the service that allows users to create their own Internet radio stations, is the little music search engine that could, then founder Tim Westergren, 44, is its quixotic engineer. A former rock and jazz musician, Westergren had a big idea in 1999: the Music Genome Project, a typology for categorizing any piece of music according to nearly 2,000 traits identified by Pandora's experts. As a user, you start with, say, a Brian Eno song, then receive a stream of "genetically" related music — Four Tet, Harold Budd and other artists you'll probably like.
For years, Pandora chronically verged on failure. But thanks to the iPhone, 15 million of which carry a Pandora app, it has finally made it over the top — and Westergren and his hybrid of human discernment and digital power are successful as well as cool.
Andersen is a novelist and host of public radio's Studio 360
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