  We highlight some recent developments that widen the scope and reach of
mesoscopic thin-film (or long-wave) hydrodynamic models employed to describe
the dynamics of thin films, drops and contact lines of simple and complex
liquids on solid substrates. The basis of the discussed developments is the
reformulation of various mesoscopic thin-film hydrodynamic models as gradient
dynamics on underlying energy functionals. After briefly presenting the general
approach, the following sections discuss how to improve these models by
amending the energy functional and the mobility function, how to obtain
gradient dynamics models for some complex liquids, and how to incorporate
processes beyond relaxational dynamics.
