  We elucidate some properties of the relation between two T-dual systems in
tori, branes at angles and branes wrapping the whole torus carrying fluxes. We
analyze different features of these systems: charges, low energy spectrum,
tadpole cancellation, symmetry groups, ... and the correspondence between the
two viewpoints. Particular attention is paid to supersymmetry and stability
conditions. While on the branes at angles side stability and supersymmetry can
be expressed as conditions on the angles between the two branes at the
intersection, on the dual side supersymmetry has to do with a correction to
Hermite Yang-Mills and a modified notion of stability should be considered.
