2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/21865The login time distribution in e-mail servers are studied. The distribution seems to be decaying in a scale-free manner with a decay exponent lying between 1.2 and 2.2, varying from server to server. A simple mean-field theory shows that this distribution has a decay exponent 2.2 pages, 1 eps figure, RevTeX4Statistical Mechanicstext