The use of equipartition calculations in estimating magnetic field strengths and energetics of extragalactic radio sources is widespread and well known. Since it is one of the few ways in which to calculate radio source parameters, it is important to determine how reasonable the approach generally is. Since this assumption is approximately a minimum energy criterion one expects that deviations from equipartition are limited at some level by independently determined constraints on the total energy. In this regard we have analyzed radio images of nearby spiral galaxies in order to determine equipartition magnetic fields and relativistic gas energies and to explore their possible nonequipartition configurations.