  It was proposed earlier that the relativistic ejections observed in
microquasars could be produced by violent magnetic reconnection episodes at the
inner disk coronal region. Here we revisit this model, which employs a standard
accretion disk description and fast magnetic reconnection theory, and discuss
the role of magnetic reconnection and associated heating and particle
acceleration in different jet/disk accretion systems, namely young stellar
objects (YSOs), microquasars, and active galactic nuclei (AGNs).
