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Far from a Fortune 500 company in size, the 36-person startup is now one of the most-talked-about technologies in the world. As the two-year-old micro-blogging site takes hold, big businesses like Dell (No. 33) and Comcast (No. 68) are finding ways to use Twitter to move inventory, market themselves, and monitor customer complaints.

From left: Evan Williams, CEO and co-founder, Twitter; Fred Wilson, principal, Union Square Ventures; Bijan Sabat (top middle), general partner, Spark Capital; Biz Stone, co-founder, Twitter; Ted Wang (board observer), partner, Fenwick & West; Peter Fenton, general partner, Benchmark Capital; Jack Dorsey (jumping), co-founder, Twitter

Last updated April 23 2009: 4:10 PM ET
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