  All novae recur, but only a handful have been observed in eruption more than
once. These systems, the recurrent novae (RNe), are among the most extreme
examples of novae. RNe have long been thought of as potential type Ia supernova
progenitors, and their claim to this 'accolade' has recently been strengthened.
In this short review RNe will be presented within the framework of the maximum
magnitude-rate of decline (MMRD) phase-space. Recent work integrating
He-flashes into nova models, and the subsequent growth of the white dwarf, will
be explored. This review also presents an overview of the Galactic and
extragalactic populations of RNe, including the newly identified 'rapid
recurrent nova' subset - those with recurrence periods of ten years, or less.
The most exciting nova system yet discovered - M31N 2008-12a, with its annual
eruptions and vast nova super-remnant, is introduced. Throughout, open
questions regarding RNe, and some of the expected challenges and opportunities
that the near future will bring are addressed.
