"We've all encountered them. They lurk in Internet message boards, comment threads, and chatrooms. Addressing anyone and everyone, they type up lengthy tirades with Cheeto-stained fingers, extolling the virtues of their product or brand of choice. They angrily accuse even the most impartial reviewers of taking handouts from reviled competitors of a beloved company, and they casually and systematically dismiss any evidence that might conflict with their worldview. They're known in our parlance as fanboys..."