Baker, a part-time trapeze artist, is a full-time advocate for open-source software and an Internet that functions as a public resource.
ethnographer and social-media expert
Microsoft Research New England
Boyd understands better than anyone how (and why) teenagers use the Internet as an alternative social space. Early this year, she joined Microsoft's new pure research lab in Boston.
New York University's Interactive Telecommunications Program
The godmother of Silicon Alley. Burns's pioneering work in alternative media begat the "Harvard of interactive," as Newsweek once called NYU's program. Decades later, she's still shaping young minds.
University of Michigan
This Net-neutrality advocate—who speaks widely about the imperative that ISPs not have the power to control what people do and say online—co-led Obama's FCC transition team.
Dyson epitomized the digerati back in the 1990s and still blogs and writes regularly. But she now exerts influence through investments in, and board seats at, companies such as Boxbe, Meetup, and 23andMe.
Internet Identity Workshop, Identity Commons
Who we are and what we choose to share about ourselves online are part of the complex of "digital identity" issues that Hamlin—aka Identity Woman—wrestles with as the most prominent advocate for OpenID and other standards on the Web.
Hunt is known for leading online grassroots communities—such as BarCamp, the user-generated conference—and teaching companies how to foster their own Web followings. Her upcoming book, The Whuffie Factor, takes her message to the masses.
As a social-media analyst at Forrester Research, Li was an indispensible resource. Her best-selling book Groundswell (coauthored with Josh Bernoff) helped demystify the social Web. Now, she has struck out on her own with Altimeter Group, where she Tweets, blogs, speaks, and consults.
Meeker deserved the brutal downgrade she got for failing to anticipate the dotcom bust. But she has done more than survive the backlash: Meeker 2.0 is again an essential voice, offering hype-free insight and—gasp!—actual financial analysis.
A version of this article appeared in the February 2009 issue of Fast Company magazine.