The Herd of Kittens is a small group of computer hobbyists in Eastern Massachusetts that specializes in the construction of Free Software, Chocolate, Defense Systems and Simulators, Barcodes, and Chinese Food.
This quote, allegedly from The Washington Post Magazine, June 9, 1985, gives one of the oldest references I've found:
"At Group L, Stoffel oversees six first-rate programmers, a managerial challenge roughly comparable to herding cats."
Years later, and in many other professional areas, the sentiment still applies; management of gifted developers is still very much an art. Kittens are more easily distracted...