Highly spin-polarized magnets have the potential to radically improve the performance of many spintronic devices. Recent work in IRG3 by graduate student Mike Manno and undergraduate Rachel Frakie has addressed two of the biggest roadblocks to the development of such materials: Establishing reliable methods to accurately determine the polarization, and demonstrating the ability to maintain it in thin film structures. Spin polarizations up to 90 % were measured in (Co,Fe)S2 thin films using the phenomenon of intergranular tunneling (see figure).