  We apply a model of magnetically dominated coronae above standard accretion
discs to the low/hard state of galactic black holes. When the disc-corona
coupling is accounted for self-consistently assuming that magneto-rotational
instability is at work in the disc, and that the corona is generated by buoyant
escape of disc magnetic structures, then the model predicts powerful, X-ray
emitting coronae at low accretion rates. A main consequence is discussed: the
possibility that the corona itself is the launching site of powerful, MHD
driven jets/outflows. This depends crucially of the coronal scaleheight.
Finally, we present the first radial profiles of a corona a different accretion
rates, and discuss their implications for high frequency variability.
