"When I first started working for Larry Summers, then chief economist at the World Bank, he was married to a tax attorney, Vicki. He was very supportive of Vicki's career and used to urge her to "bill like a boy." His view was that the men considered any time they spent thinking about an issue--even time in the shower--as billable hours. His wife and her female colleagues, however, would decide that they were not at their best on a given day and discount hours they spent at their desks to be fair to the client. Which lawyers were more valuable to that firm? To make his point, Larry told them the story of a renowned Harvard Law School professor who was asked by a judge to itemize a bill. The professor responded that he could not because he was so often thinking about two things at once."