  Charge-density-wave dynamics is studied on a submicron length scale in NbSe_3
and o-TaS_3. Regions of negative absolute resistance are observed in the CDW
sliding regime at sufficiently low temperatures. The origin of the negative
resistance is attributed to the different forces that the deformed CDW and
quasi-particles feel: the force on the CDW is merely caused by a difference of
the electric potentials, while the quasi-particle current is governed by a
difference of the electrochemical potentials.
