Due to advances in technology and the rapid growth of online services, a significant number of new and inventive web-based service models and delivery methods have been introduced. Although online resources and services are having an impact on more traditional service delivery mechanisms, it is not yet clear how these emerging mechanisms for online service delivery will result in profitable business models. In this paper, we consider emerging business models for online services and their implications for how services are delivered, used, and paid for. We demonstrate the changing roles of user / consumer and provider / seller. We also discuss the applicability of different business models for various domains.