The interface between a living cell and the surrounding world plays a critical role in numerous complex biological processes. Sperm/egg fusion, virus/cell fusion, exocytosis, endocytosis, and ion permeation are a few examples of processes involving membranes. In recent years, powerful tools such as X-ray crystal- lography, electron microscopy, nuclear magnetic resonance, and infra-red and Raman spectroscopy have been developed to characterize the structure and dy- namics of biomembranes. Despite this progress, many of the factors responsible for the function of biomembranes are still not well...