  We demonstrate several examples of driving and steering of colloids when
dispersed in nematic liquid crystals. The driving mechanism is based on the
principle of nonlinear electrophoresis which is mediated by the asymmetry in
the structure of the defects that the inclusions generate in the host elastic
matrix. The steering mechanism originates in the photoactivation of the
anchoring conditions of the nematic liquid crystal on one of the enclosing
plates. As experimental realizations we first review a scenario of water
microdroplets being phoretically transported for cargo release and chemical
reaction. Steering is illustrated in terms of the reconfigurable assembly of
colloidal particles, either in the form of asters or rotating-mills, commanded
by predesigned patterns of illumination.

Soft Condensed Matter