Is e-mail obsolete? As a matter of fact, we tend to gather more and more information in our inboxes: personal and professional communications, but also marketing and commercial ads, alerts and notifications from websites or social networks, search engines results, agendas, ... The current use also tends to widen: e-mail is not only used to fulfill inter-personal communication but also to exchange files, to gather RSS feeds or to pick up a date for a meeting. Many people rely on their inboxes to retrieve important information and to organize their daily work.