A method of producing nanoparticles can comprise milling a plurality of milling bodies sufficient to produce the nanoparticles from exterior surfaces of the plurality of milling bodies. In this manner, the milling bodies are simultaneously the milling media and the feedstock for production of nanoparticles such that additional solids are not present during milling. Nanoparticles can be readily formed and optional milling agent and capping agents can be provided to stabilize and/or customize the nanoparticles for a particular application.