Local Group and Star Cluster Dynamics from HSTPROMO (The Hubble Space
  Telescope Proper Motion Collaboration)
  The Hubble Space Telescope (HST) has proven to be uniquely suited for the
measurement of proper motions (PMs) of stars and galaxies in the nearby
Universe. Here we summarize the main results and ongoing studies of the
HSTPROMO collaboration, which over the past decade has executed some two dozen
observational and theoretical HST projects on this topic. This is continuing to
revolutionize our dynamical understanding of many objects, including: globular
clusters; young star clusters; stars and stellar streams in the Milky Way halo;
Local Group galaxies, including dwarf satellite galaxies, the Magellanic
Clouds, and the Andromeda galaxy; and AGN Black Hole Jets.
