  We study the dynamical properties of active polar liquid crystalline films.
Like active nematic films, active polar films undergo a dynamical transitions
to spontaneously flowing steady-states. Spontaneous flow in polar fluids is,
however, always accompanied by strong concentration inhomogeneities or
"banding" not seen in nematics. In addition, a spectacular property unique to
polar active films is their ability to generate spontaneously oscillating and
banded flows even at low activity. The oscillatory flows become increasingly
complicated for strong polarity.
