Nearly a decade after its retirement, the advice-spewing "Clippy" remains one of technology's most hated characters. As part of Microsoft's Office Assistant help system, the paperclip-faced avatar proposed help based on Bayesian probability algorithms: start a word-processing document with "Dear," and it offered to help you write a letter. Express exasperation, and Clippy would gleefully continue pestering you: it could not sense your mood.
Perhaps Clippy would still be with us if it had employed affective computing, a growing field that attempts to determine a user's mood or emotion through visual, auditory, physiological, and behavioral cuescues that comprise one's "affect." An affect-enabled Clippy might see your look of disgust and make itself scarce; conversely, it might pop up sooner when you furrow your brow in confusion.