An abstract was not provided in the original work, so a preliminary abstract has been prepared as follows. Recent advances in experimental techniques allow us to solve ever larger 3D biomolecular structures. However, static states often lack dynamic information that is crucial for understanding subtle mechanisms at the molecular level. New simulation approaches specifically designed to study the formation and stability of very large biological structures need to be developed. BioSpring is unconventional and innovative software designed for molecular sketching and modeling. The main goals of BioSpring are to provide a tool to interactively get a quick overview of biomechanical properties, to support the user in the complex task of modeling large biomolecular complexes, to perform interactive flexible docking, and to provide and explore new hypotheses for complex molecular assemblies.