  We predict two spin-dependent transport phenomena in two-dimensional electron
systems, which are induced by spatially fluctuating Rashba spin-orbit
interaction. When the electron gas is magnetized, the random Rashba interaction
leads to the anomalous Hall effect. An example of such a system is a narrow-gap
magnetic semiconductor-based symmetric quantum well. We show that the anomalous
Hall conductivity reveals a strongly nonlinear dependence on the magnetization,
decreasing exponentially at large spin density. We also show that electron
scattering from a fluctuating Rashba field in a two-dimensional nonmagnetic
electron system leads to a negative magnetoresistance arising solely due to
spin-dependent effects.
