This article discusses how new technologies of communication, especially the Internet and, more specifically, social network services, can interfere in social interactions and in political relations. The main objective is to problematize the concept of public liberty and verify how the new technologies can promote the reoccupation of public spaces and the recovery of public life, in opposition to the tendency to valorize the private sphere, observed in the second half of the twentieth century. The theoretical benchmark adopted for the investigation is Hannah Arendt's theory about the exercise of fundamental political capacities in order to establish a public space of freedom, as presented in “On Revolution”. The “Praia da Estação” (“Station Beach”) case is chosen to test the hypothesis. In 2010 in the Brazilian city of Belo Horizonte, different individuals articulated a movement through blogs, Twitter and facebook, in order to protest against the Mayor’s act that banned the assembling of cultural events in one of the main public places of the city, the “Praça da Estação” (Station Square). By applying Arendt's concepts to the selected case, it is possible to demonstrate that the Internet can assume an important role against governmental arbitrariness and abuse of power, as it can stimulate the public exercise of fundamental freedoms, such as freedom of assembly and manifestation.