For technologists, electric utilities provide an irresistible proving ground for a never-ending stream of high tech toys.  The markets are huge, the product ubiquitous, and the current technology base is surprisingly archaic.  Among all of the toys, the 'golden fleece' on everyone's radar screen for the last 20 years has been the 'customer interface'.   What technology will become the instrument for linking customers to their service providers and applications?  Electronic gateways and advanced meters are the two principal contestants.   Gateways combine communications, control theory, networking, automation and many very interesting business opportunities.  Advanced meters are rather mundane instruments for recording energy usage and not much more.   However, meters and gateways have a common ground: they both facilitate demand response.   So which technology option will prevail?  Is there a market for gateways and if so, why have all efforts to bring them to market failed?  Is there a market for advanced meters and if so, why haven't the compelling benefits of the last few years motivated more widespread implementation?