Intense muon beams and neutrino factories

High intensity muon sources are needed in exploring neutrino factories, lepton flavor violating muon processes, and lower energy experiments as the stepping phase towards building higher energy μ+μ- colliders. We present a brief overview, sketch of a neutrino source, and an example of a muon storage ring at BNL with detector(s) at Fermilab, Sudan, etc. Physics with low energy neutrino beams based on muon storage rings (μSR) and conventional Horn Facilities are described and compared. CP violation Asymmetries and a new Statistical Figure of Merit to be used for comparison is given. Improvements in the sensitivity of low energy experiments to study Flavor changing neutral currents are also included