  We present our results of Monte-Carlo simulations of polarized Compton X-rays
from magnetic cataclysmic variables, with realistic density, temperature and
velocity structures in the accretion flow. Our study has shown that the X-ray
linear polarization may reach about 8% for systems with high accretion rates
viewed at a high viewing inclination angle. This value is roughly twice the
maximum value obtained by previous studies which assumed a cold, static
emission region with a uniform density. We also investigate the X-ray
polarization properties of ultra-compact double-degenerate binaries for the
unipolar-inductor and direct-impact accretor models. Our study has shown
negligible X-ray polarization for the unipolar-induction model. However, the
direct-impact accretor model may give X-ray polarization levels similar to that
predicted for the magnetic cataclysmic variables.
