The small size and power consumption of IEEE 802.15.4 devices allows embedding them in GSM/UMTS U-SIM cards and/or SD cards. The availability of such technology for data exchange within mobile phones is very useful to complement GSM/UMTS services, providing proximity services, such as chat and advertisements in a shopping mall, configuration data, micro-payments, access control. In addition, once that we have the availability of a free communication radio link, we can enlarge the assortment of offered services, supporting not only direct data exchanges between two users within the 802.15.4 connectivity range, but also communication among intermittently connected users. This is a typical scenario of so-called Delay Tolerant Networks (DTN) and we argue that a communication paradigm well suited to this environment is publish-subscribe. On the other hand, publish-subscribe is also well suited to satisfy the requirements of a community of users such as the one of an university campus, accompanying other services such as voice and Internet access. The aim of this paper is to present a topic-based, publish-subscribe architecture for intermittently connected networks exploiting IEEE 802.15.4 devices, and taking into due account the severe constraints deriving from their physical characteristics. We describe the architectural model, the protocol design, the system analysis, and the implementation of our solution in a real test-bed, which we carried out in cooperation with Telecom Italia, that financed this work. We point out that our system can be easily adapted to operate in a fully distributed, infrastructure-less way, allowing free communications e.g. in disaster areas or in areas in which usual communications means are either non existent or intentionally made unavailable. For instance, we could realize a server-less version of Twitter able to epidemically distribute information very quickly, provided that we have a high-enough density of devices implementing our solution. © 2011 IIMC.