  We investigate the role of stellar mass in shaping the intrinsic thickness of
faint systems by determining the probability distribution of apparent axis
ratios for two different samples that probe the faint end of the galaxy
luminosity function (M_B < -8). We find that the (b/a) distribution is a strong
function of M*, and identify a limiting stellar mass M* ~ 2x10^9 Msun below
which galaxies start to be systematically thicker. We argue that this is the
result of the complex interplay between galaxy mass, specific angular momentum
and stellar feedback effects: the increasing importance of turbulent motions in
lower mass galaxies leads to the formation of thicker systems. We find a good
agreement between our results and the latest numerical simulations of dwarf
galaxy formation, and discuss several further implications of this finding
--including the formation of bars and spirals in faint galaxies, the
deprojection of HI line profiles and simulations of environmental effects on
dwarf galaxies.
