From Adam Goodheart’s “10 Days That Changed History” (The New York Times: 2 July 2006):
SEPT. 18, 1957: Revolt of the Nerds
Fed up with their boss, eight lab workers walked off the job on this day in Mountain View, Calif. Their employer, William Shockley, had decided not to continue research into silicon-based semiconductors; frustrated, they decided to undertake the work on their own. The researchers  who would become known as “the traitorous eight”  went on to invent the microprocessor (and to found Intel, among other companies). “Sept. 18 was the birth date of Silicon Valley, of the electronics industry and of the entire digital age,” says Mr. Shockley’s biographer, Joel Shurkin.