Far from playing only the role of bricks and mortar as a mere divider between the inside and outside of cells or between parts of the cell, lipid bilayers are an active, tightly regulated cellular component whose physical properties are critical for the proper function of the membrane proteins contained within them. Lipid bilayers are the preeminent domain of computational biology since despite their considerable stability and impenetrability they form disordered films that are best described through computer modeling, albeit tested by observation. One of the largest molecular modeling projects achieved so far has been recently reported that employed NAMD to investigate the mechanical properties of cellular membranes. The systems simulated were made of lipids and water, composed of about 40,000 atoms, and simulated for over 100 nanoseconds. The simulations revealed that membranes, in terms of their mechanical properties, are far from being homogenous films; rather, they exhibit a delicate multi-lamellar structure of layers that alternatively tend to shrink and expand the membrane, inducing strong forces on all proteins and molecules entering. The lamellar character of the cell's membranes plays a key role for cellular processes such as osmotic regulation and may explain even the action of anaesthetics.