Worldwide research on devices for tomorrow's spintronic logic and storage continues apace. The authors use $a\phantom{\rule{0}{0ex}}b$ $i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}o$ calculations to investigate the electronic structures, magnetic properties, and tunneling magnetoresistance (TMR) effect of magnetic tunnel junctions based on the ferromagnetic nitrides ${M}_{4}$N ($M$ = Fe, Co, Ni). The case of iron presents a half-metallic state, and an ultrahigh TMR ratio greater than 24,000%---strong motivation for experimentalists.