The Sunyaev Zel’dovich (SZ) effect, temperature/polarization anisotropies and spectral distortions in the cosmic microwave background (CMB) induced by scattering from free electrons in the post-reionization Universe, is a primary target of current and future CMB instruments. Increasingly precise measurements of the SZ effect promise to greatly inform our understanding of the distribution of baryons in the cosmos. In addition, when combined with the next generation of galaxy surveys, the SZ effect has enormous potential to improve our understanding of fundamental cosmology. In this talk I will demonstrate how cross correlations between galaxy surveys and low-noise high-resolution observations of the CMB can be used to reconstruct the velocity and density fields on scales which are currently measured using the primary CMB anisotropies. I will then discuss how such a reconstruction could be used to resolve long-standing ‘anomalies’ in the primary CMB, constrain the properties of dark energy, and improve constraints on primordial non-gaussianity.