Age: 33
Occupation: General manager, Reddit
Reddit, the self-proclaimed "front page of the Internet," hit a pretty huge milestone in December: 2 billion page views in a single month, more than any but a handful of sites worldwide. Reddit's massive community of users, who vote up or down on stories, links, memes and videos, showed a social conscience this year: under Martin's lead, it was instrumental in organizing opposition to proposed SOPA and PIPA antipiracy laws, even going dark in protest along with other sites on Jan. 18.