  It has been noted that the Crab and Vela pulsar proper motions lie along the
symmetry axes of their wind nebulae. In an effort to promote this observation
to a serious test of kick physics, we are using CXO images and other data to
estimate the angle between the proper motion and PWN (i.e. spin) axis for a
number of pulsars. Here we give a progress report on this work and the
constraints that these data provide on kick models. Present data suggest that a
kick duration of tau_K~3s is sufficient to explain the alignment of most
pulsars. This rules out E-M and hydrodynamic kick models, but is fairly
consistent with proposed anisotropic neutrino emission. However, some objects,
especially PSR J0538+2817 show such good alignment that even neutrino models
are challenged.
