Abstract
We study the behavior of wave propagation in materials for which not all of the principal elements of the permeability and permittivity tensors have the same sign. We find that a wide variety of effects can be realized in such media, including negative refraction, near-field focusing, and high impedance surface reflection. In particular, a bilayer of these materials can transfer a field distribution from one side to the other, including near fields, without requiring internal exponentially growing waves.