Employing intense muon sources to carry out forefront low energy research, such as the search for muon - number non-conservation, or for the purpose of providing intense high energy neutrino beams ((nu)factory) represents very interesting possibilities. If successful, such efforts would significantly advance the state of muon technology and provides intermediate steps in technologies required for a future high energy muon collider complex. High intensity muon: production, capture, cooling, acceleration and multiturn muon storage rings are some of the key technology issues that needs more studies and development. A muon collider require basically same number of muons as for the muon storage ring Neutrino Factory, but would require more cooling, and simultaneous capture of both (+-)(mu). We present an overview of Muon Sources - Neutrino Factories, example of a muon storage ring at BNL, and possible upgrades to a full Muon Collider.