The corporation behind the Positronic Brain technology which made possible all of the robots featured in Isaac Asimov's books and stories. The full title is US Robotics and Mechanical Men, but the title is frequently abbreviated.

Some years later a certain real-life modem company happened to name themselves after US Robotics as some kind of a tribute. This meatspace US Robotics is most well known for its brief ownership of Palm Computing (U.S. Robotics bought Palm, then was itself purchased by 3com, which then spun Palm Computing off).

Thanks to generic-man for correcting an inaccuracy in this post