This paper presents a complete system for anticipating road hazard based on inter-vehicular communication. It relies on efficient cooperative strategies between vehicles, namely distributed data fusion for hazard detection and conditional transmissions for alert propagation. It is built upon cheap embedded hardware and specific embedded software dedicated to dynamic vehicular networks. We describe the system, its architecture and the cooperative strategies. Road experiments involving 10 vehicles are reported. Real-life in-lab experiments complete the study with performance evaluation. These experiments emphasize the complementarity of both cooperative strategies. They show the practical interest of the whole system as well as its truthfulness and robustness even against poor networking conditions. They prove its efficiency to provide a significant anticipation period of road hazards.