  Directional detection can provide unambiguous observation of Dark Matter
interactions even in presence of insidious backgrounds. The DM-TPC
collaboration is developing a detector with the goal of measuring the direction
and sense of nuclear recoils produced in Dark Matter interactions. The detector
consists of a Time Projection Chamber with optical readout filled with CF$_4$
gas at low pressure. A collision between a WIMP and a gas molecule results in a
nuclear recoil of 1-2 mm. The measurement of the energy loss along the recoil
allows us to determine the sense and the direction of the recoil.
  Results from a prototype detector operated in a low-energy neutron beam
clearly demonstrate the suitability of this approach to measure directionality.
A full-scale module with an active volume of about one cubic meter is now being
designed. This detector, which will be operated underground in 2009, will allow
us to set competitive limits on spin-dependent Dark Matter interactions using a
directional detector.
