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4. Cisco Systems
Cisco Systems
Fortune 500 rank: 57

The convergence of data, voice and video is spurring companies to upgrade their networks with the Internet router and switch giant's products.

Sales of Cisco's advanced technology products, like its TelePresence video-conferencing system, helped profits rise 9.8% to $8 billion on sales of $39.5 billion.

NEXT: Oracle
Last updated April 29 2009: 1:31 PM ET
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