1. A method, comprising: retrieving a file that includes mark-up language code which, when interpreted by a browser, would cause the browser to render original page content for a page designed by a first party; a second party that is different from said first party using a tool to insert executable code into the file to create a code-injected file; interpreting at least a portion of the code-injected file to produce generated content; wherein interpreting at least said portion includes executing at least some of the inserted executable code; wherein executing at least some of the inserted executable code includes executing inserted executable code that (a) modifies how executable code that originated in the file is executed; (b) excludes from the generated content a subset of the original page content; (c) generates new content that would not be in said original page content; or (d) simulates at least one user event; and providing at least a portion of the generated content to a particular application that performs operations based on the portion of the generated content.