  We present a brief review of the physical properties of Sr3Ru2O7, in which
the approach to a magnetic-field-tuned quantum critical point is cut off by the
formation of a novel phase with transport characteristics consistent with those
of a nematic electronic liquid crystal. Our goal is to summarize the physics
that led to that conclusion being drawn, describing the key experiments and
discussing the theoretical approaches that have been adopted. Throughout the
review we also attempt to highlight observations that are not yet understood,
and to discuss the future challenges that will need to be addressed by both
experiment and theory.
