Canadian singer-songwriter Dave Carroll turned a customer-service debacle into YouTube celebrity with his anti–United Airlines crusade. In two music videos, Carroll calls out United for manhandling his $3,500 guitar at Chicago's O'Hare airport and not offering compensation or repair. Anyone with a bad airline experience can relate, as the video's more than 7 million views show. Eventually United offered Carroll compensation, but Carroll, who recently started a forum for users to share customer experiences, claims his new guitar just doesn't sound the same.