1. A server system for providing one or more services, the server system comprising one or more computer-readable media having computer-executable instructions for implementing a method for dynamically executing one or more filtering functions at any of one or more processing steps that may occur in providing the one or more services to one or more client systems, wherein the method comprises: an act of defining one or more processing steps that are performed by a server system in providing one or more services in response to a request, the one or more processing steps being defined within a plurality of processing layers of the server, the plurality of processing layers including at least a parsing layer; an act of dynamically assigning at least one filtering function to at least one of the one or more processing steps, wherein the filtering function is configured to terminate further processing based on content in the request; at each processing step that is processed, an act of dynamically evaluating whether or not any filtering function has been assigned; and at each processing step that is processed and has at least one assigned filtering function, an act of executing the at least one assigned filtering function by terminating further processing when the request contains particular content.