  We study the behavior of the quarter-filled Kondo lattice model on a
triangular lattice by combining a zero-temperature variational approach and
finite-temperature Monte-Carlo simulations. For intermediate coupling between
itinerant electrons and classical moments ${\bf S}_j$, we find a thermodynamic
phase transition into an exotic spin ordering with uniform scalar spin
chirality and $< {\bf S}_j >=0$. The state exhibits spontaneous quantum Hall
effect. We also study how its properties are affected by application of an
external magnetic field.
