  An off-lattice Monte Carlo algorithm for solutions of equilibrium polymers
(EP) is proposed. At low and moderate densities this is shown to reproduce
faithfully the (static) properties found recently for flexible linear EP using
a lattice model. The molecular weight distribution (MWD) is well described in
the dilute limit by a Schultz-Zimm distribution and becomes purely exponential
in the semi-dilute limit.
  Additionally, very concentrated molten systems are studied. The MWD remains a
pure exponential in contrast to recent claims. The mean chain mass is found to
increase faster with density than in the semi-dilute regime due to additional
entropic interactions generated by the dense packing of spheres.
  We also consider systems in which the formation of rings is allowed so that
both the linear chains and the rings compete for the monomers. In agreement
with earlier predictions the MWD of the rings reveals a strong singularity
whereas the MWD of the coexisting linear chains remains essentially unaffected.
