Physics-based modeling techniques have been shown to be advanced methods for creating high quality surfaces for application in CAGD. In this paper we propose a physics-based Temporal Computational Object (TCO) as a modeling process that simulates a liquid membrane to generate organic freeform models. This process compliments existing solid and elastic physics based modeling processes by simulating a common liquid phase of matter. The simulation consists of a mesh that undergoes motion in response to surface tension and other energies, resulting in a smooth, minimum energy surface. The surface is produced via a dynamic process that is directed and influenced by user-defined scalar and vector fields, boundary conditions and a variety of internal parameters and topologies. These surfaces include multiple free intersecting surfaces, volume-preserving surfaces and periodic surfaces. We provide a wide range of examples that show high quality physics-based surfaces.