Since the pioneering discoveries of Hodgkin, Huxley, and Katz, it has been clear that specific ion conductance pathways underlie electrical act- ity. Over the ensuing 50 years, there has been ever increasing, and occasi- ally explosive, changes in the scope of efforts to understand ion channel behavior. The introduction of patch clamp technology by Erwin Neher and Bert Sakmann about 20 years ago led to the realization of the great variety of novel ion channel species, and the subsequent revolution in cl- ing has revealed an even greater diversity of the underlying molecular entities. Today,...