An integrated, reconfigurable, adaptable and open system for mining, indexing and retrieving multimedia information based on a mobile agent technology scheme is presented. The system consists of three integral subsystems, namely the acquisition, the transformation and the distribution modules. Innovative algorithms are used to extract information from web sources, transform it and deliver it to the end users. The system supports efficient content adaptation mechanisms, textual and visual summarization schemes (both sequential and hierarchical), automatic language translation, ontological representation, visual processing and web-based data mining. Experimental analysis on real-life web sites has been performed to test the efficiency of the proposed scheme and compare it with other approaches presented in the literature.