The main topic of this HDR is the design and the analysis of information delivery systems in the context of challenging environments and disruptive usage patterns. The driving motivation of the work I will present can be stated as follow: How to handle the mobility in its many incarnations, whether we consider the migration or replication of content between fixed repositories or the movements of the hosting nodes if mobile? In this presentation, I will address the mobility, first as a challenge and then, as an enabler. The contributions of this HDR are organized into two main parts: * Content, the big ‘C’ of computer networking This first part consists of three pieces of work related to content delivery in the context of various environments. We first consider the core of large-scale conventional networks such as the Internet. We address the limitations resulting of the host-centric design of the Internet. We propose a query-based search approach that leverages the replication of popular content. In a second piece of work, we address the mismatch between the available capacity of cellular wireless networks and the increasing demand for content on the move. We propose a radio resource-saving strategy for disseminating delay-tolerant content in cellular environments. In the third and last work of this part, we address the problem of disseminating content in vehicular networks. * Tapping into everyday mobility: This second part presents a number of contributions that take advantage of the alternative communication channel resulting of the movements of entities such as vehicles equipped with storage capabilities. We use this alternative communication channel to supplement or in replacement of conventional infrastructure-based data networks. We exploit the existing mobility of surrounding entities to overcome various limitations of conventional data networks. In a first work, we use the routine journeys daily taken by private cars equipped with data storage devices to extend cost-effectively the capacity of the Internet. In the second and last work, I present two vehicular cloud services exploiting the mobility of public transit buses in urban scenarios.