Severe plastic deformation (SPD), i.e. intense plastic straining under high pressure, is an innovative technique for producing ultrafine-grained nanostructured metals and alloys. SPD-produced nanostructures can lead to extraordinary properties which, however, depend strongly on the microstructure features and processing parameters. The present paper focuses on examples of SPD-processed metallic nanomaterials with such unique functional and mechanical properties as very high strength and ductility, superplasticity and shape memory effect. The processing-nanostructures-new properties relationship in SPD-produced materials is considered and discussed.