  Due to the recent experimental progress, tunable spin-orbit (SO) interactions
represent ideal candidates for the control of polarization and dynamical spin
properties in both quantum wells and cold atomic systems. A detailed
understanding of spin properties in SO coupled systems is thus a compelling
prerequisite for possible novel applications or improvements in the context of
spintronics and quantum computers. Here we analyze the case of equal Rashba and
Dresselhaus couplings in both homogeneous and laterally confined
two-dimensional systems. Starting from the single-particle picture and
subsequently introducing two-body interactions we observe that periodic spin
fluctuations can be induced and maintained in the system. Through an analytical
derivation we show that the two-body interaction does not involve decoherence
effects in the bosonic dimer, and, in the repulsive homogeneous Fermi gas it
may be even exploited in combination with the SO coupling to induce and tune
standing currents. By further studying the effects of a harmonic lateral
confinement --a particularly interesting case for Bose condensates-- we
evidence the possible appearance of non-trivial {\it spin textures}, whereas
the further application of a small Zeeman-type interaction can be exploited to
fine-tune the system polarizability.
