  We study electron transport through a semiconductor superlattice subject to
an electric field parallel to and a magnetic field perpendicular to the growth
axis. Using a single miniband, semiclassical balance equation model with both
elastic and inelastic scattering, we find that (1) the current-voltage
characteristic becomes multistable in a large magnetic field; and (2) ``hot''
electrons display novel features in their current-voltage characteristics,
including absolute negative conductivity (ANC) and, for sufficiently strong
magnetic fields, a spontaneous dc current at zero bias. We discuss possible
experimental situations providing the necessary hot electrons to observe the
predicted ANC and spontaneous dc current generation.
