want to know how your organisation really works? Study the flow of internal e-mails, say scientists from the us-based technology firm Hewlett-Packard. The researchers have developed a way to use e-mail exchanges to build a map of the structure of an organisation. The map shows the teams in which people actually work, as opposed to those they are assigned to. The technique also reveals who is at the heart of each sub-group. Employees often correspond with designated leaders. But unofficial