Ultra-cold Plasmas obtained by ionization of atomic Rydberg states are qualified as classical and strongly coupled electron fluid. They are shown to share several common trends with ultra-cold electron flows used for ion beam cooling. They exhibit specific stopping behavior to charged particle beams, which may be used for diagnostics purposes. Ultra-cold plasmas are easily strongly magnetized. Then, one expects a strongly anisotropic behavior of low ion velocity slowing down when target electron cyclotron radius turns smaller than corresponding Debye length.