Spintronics leverages electron spins to enhance solid-state devices by prolonging battery life. Spintronic developments, however, are increasingly running up against the Slater-Pauling limit, the maximum for how tightly a material can pack its magnetization. Now, a new thin film is poised to break through this decades-old benchmark. Researchers now discuss their work constructing a stable thin film made from iron, cobalt and manganese that may push past the Slater-Pauling limit.