1. A system for providing usage billing of streamed hosted applications, the system comprising: one or more memory storage locations configured to store the hosted applications and executables; one or more computer servers each with a host operating system configured to stream said hosted applications to one or more clients; one or more clients each with a client operating system configured to receive and execute said streamed hosted applications, and configured to operate a local billing manager; and one or more billing interceptors operating at or above the host operating systems level and configured to intercept access to resources and interfaces of said one or more client operating systems; said billing interceptors are loaded when the streamed applications are loaded on said one or more clients, and said billing interceptors are loaded into the address spaces of each of the streamed applications without requiring any application customizations; wherein said hosted applications are streamed to said one or more clients.