  This paper provides two families of flexible and simple galaxy models.
Representatives of many of the families possess the important cosmological
cusps, with the density behaving like 1/r or 1/r^1.33 or 1/r^1.5 at small
radii. The density falls off between 1/r^3 and 1/r^5 at large radii. We provide
analytic and anisotropic distribution functions for all the models. Unlike many
existing methods, our algorithm can yield tangentially anisotropic velocity
dispersions in the outer parts, and so is useful for modeling populations of
satellite galaxies and substructure in host galaxy halos. As an application, we
demonstrate the degeneracy between mass and anisotropy for the satellite galaxy
population of the Milky Way. This can introduce a factor of ~3 uncertainty in
the mass of the Milky Way as inferred from the kinematics of the satellite
population.
