Nickname of Bruce Tognazzini.
Bruce was Apple Computer employee #66. He developed the first version of the "Apple Human Interface Guidelines" in 1978, and is still a guiding light in the field of human-computer interaction. He is currently working with the Nielson Norman Group (usability gurus).
Tog is a lot of fun to hear talking on his subject, and his book on interface design ("Tog on Interface") is an excellent read.
His website is www.asktog.com, and it contains some excellent articles, including "When Interfaces Kill", and "How I made a small fortune (out of a much larger one)".