  Effects of supersymmetric particles may appear in various low energy
experiments through loop diagrams. We discuss various flavor changing neutral
current processes, the muon anomalous magnetic moment and lepton flavor
violation in the context of the supergravity model. In particular the
$B^0$-$\ol{B}^0$ mixing and the muon anomalous magnetic moment are revisited
taking into account the recent Higgs boson search result. We also consider
$\mu^+ \to e^+ \gamma$ and $\mu^+ \to e^+ e^+ e^-$ processes with polarized
muons. We calculate the P-odd and T-odd asymmetries in these processes for
SU(5) and SO(10) supersymmetric grand unified theories and show that these
asymmetries are useful to distinguish different models.
