Plerionic Supernova Remnants
  Plerions represent ideal laboratories for the search for neutron stars, the
study of their relativistic winds, and their interaction with their surrounding
supernova ejecta and/or the interstellar medium. As well, they are widely
believed to represent efficient engines for particle acceleration up to the
knee of the cosmic ray spectrum (at about 1E15 eV). Multi-wavelength
observations from the radio to the highest TeV energies, combined with
modelling, have opened a new window to study these objects, and particularly
shed light on their intrinsic properties, diversity, and evolution.
High-resolution X-ray observations are further revealing the structure and
sites for shock acceleration. The missing shells in the majority of these
objects remain puzzling, and the presence of plerions around highly magnetized
neutron stars is still questionable. I review the current status and statistics
of observations of plerionic supernova remnants (SNRs), highlighting combined
radio and X-ray observations of a growing class of atypical, non Crab-like,
plerionic SNRs in our Galaxy. I will also briefly describe the latest
developments to our high-energy SNRs catalogue recently released to the
community, and finally highlight the key questions to be addressed in this
field with future high-energy missions, including Astro-H in the very near
future.
