The irreversible entrapment of anisotropic colloidal particles at fluid-fluid interfaces can be exploited to make permeable capsules, to stabilize foams and emulsions, and to make two-dimensional functional materials by assembling colloidal building blocks. In collaboration with Prof. Stebe (Dept. of Chem. Eng, University of Pennsylvania), I study the mechanical properties of these capillary systems. Ours is a concerted effort that relies on simulation, theory and experiments.