Recently one of the tightest limits was placed on the sum of the neutrino masses. This was an upper bound of 0.28 eV at the 95% confidence level. However, this result was not the consequence of a new particle physics experiment. Instead it was derived from observations of galaxies over the largest reaches of the observable Universe. I will describe what goes into such a project with an overview of the cosmological model and the significant physical effects that these elusive neutrinos alter. In addition, I will highlight the uncertainties and caveats of such an ambitious attempt to measure the neutrino mass. Finally, I will describe plans for the future and the importance of this interplay between particle physics and cosmology.