For technological development, and to meet new demands of tomorrow's society, there is a constant need for new materials with new or improved properties. Recently, the perovskite-like rare-earth manganese compounds have been an intensive topic in scientific studies and potential technological application because of their charge and orbital ordering, magnetic phase transitions, colossal magnetoresistance CMR effect as well as magnetocaloric effect MCE. Potential applications of the CMR effect in mixed-valence manganites include magnetic sensors; magnetoresistive read heads; and magnetoresistive random access memory. Manganites play an important role as electrodes in solid oxide fuel cells and they may also be used for catalysis and in oxygen sensors as well as hydrogen storage. MCE effect has been applied widely for magnetic refrigeration technology. Perovskites with excellent dielectric properties at the microwave frequency have been used as dielectric resonators in wireless communication system. Nanoparticles materials can offer unprecedented interactions with biomolecules both on the surface and inside the cells, which may revolutionize cancer diagnosis and treatment.