In this month's Fast Company, there's an article with comedian Lewis Black and his experiences as a customer, illustrating the good and the (all too often) bad. In the article, he offers the Rage Curve, an analysis of "what drives people nuts about automated telephone systems."
"So what makes Black happy? An honest answer. A warm reception. A little humanity. He has nothing but love for his travel agent, Brian, for example: The man's a miracle worker. And Black still talks about how some tender soul at Continental once ushered him into its Presidents Club lounge while solving a ticket problem (companies desperate to stay afloat give great service, he points out).
"He concedes that service tends to improve at the "snot end of the spectrum," and now that he has money, Black sees it more often--a fact this self-described "union guy" finds a little unsettling. "The closest the middle class can get to it is Nordstrom," he says. "I like to shop at Nordstrom--it's just my feminine side." Even when the store doesn't have the pants he wants (in, what else, black), "they go, 'I'll check to see if we can have another store ship them to you--I'll call you.' And then they call!"
IMHO, everyone who interacts with customers should have a copy of his Rage Curve within viewing range:
Source: Customer Care Management & Consulting, June 2006