  Complex fluid-fluid interfaces featuring mesoscale structures with adsorbed
particles are key components of newly designed materials which are continuously
enriching the field of soft matter. Simulation tools which are able to cope
with the different scales characterizing these systems are fundamental
requirements for efficient theoretical investigations. In this paper we present
a novel simulation method, based on the approach of Ahlrichs and D\"unweg
[Ahlrichs and D\"unweg, Int. J. Mod. Phys. C, 1998, 9, 1429], that couples the
"Shan-Chen" multicomponent Lattice Boltzmann technique to off-lattice molecular
dynamics to simulate efficiently complex fluid-fluid interfaces.
  We demonstrate how this approach can be used to study a wide class of
challenging problems. Several examples are given, with an accent on
bicontinuous phases formation in polyelectrolyte solutions and ferrofluid
emulsions. We also show that the introduction of solvation free energies in the
particle-fluid interaction unveils the hidden, multiscale nature of the
particle-fluid coupling, allowing to treat symmetrically (and interchangeably)
the on-lattice and off-lattice components of the system.
