  We consider direct dark matter detection rates and investigate the difference
between a standard Maxwell-Boltzmann velocity distribution and a "realistic"
distribution like the ones extracted from numerical N-body simulations. Sizable
differences are observed when such results are compared to the standard
Maxwell-Boltzmann distribution. For a light target both the total rate and the
annual modulation are reduced by ~25%. For a heavy target the total rate is
virtually unchanged, whereas the annual modulation is modified by up to 50%,
depending on the WIMP mass and detector energy threshold. We also consider the
effect of a possible velocity anisotropy, and the effect is found to be largest
for a light target For the realistic velocity distribution the anisotropy may
reduce the annual modulation, in contrast to the Maxwell-Boltzmann case.
