  In [B. Binz, A. Vishwanath and V. Aji, Phys. Rev. Lett. 96, 207202 (2006)], a
magnetic structure that breaks time reversal symmetry in the absence of net
magnetization was proposed as an explanation for the high pressure "partially
ordered" state of MnSi. Here we make explicit the anomalous magneto-transport
properties of such a state: a magnetoresistivity which is linear and a Hall
conductance which is quadratic in the applied magnetic field. Field cooling
procedures for obtaining single domain samples are discussed. The anomalous
effects are elaborated in the case of three geometries chosen to produce
experimentally unambiguous signals of this unusual magnetic state; e.g., it is
predicted that a field in z-direction induces an anisotropy in the x-y plane.
Another geometry leads to a Hall voltage parallel to the magnetic field.
