We report on the special sub-Doppler features of high-resolution spectrosco
py in a thin cell, in conditions when the atomic free path is anisotropic a
s due to the special cell geometry. The most recent developments include li
near spectroscopy under normal incidence, an extension to transition betwee
n excited states, and the observation of atoms flying under grazing inciden
ce in a pump-probe scheme with spatially separated beams.