9. The system of claim 7 wherein said receiving computer is a client computer.
7. A system for creating and providing a markup language document, comprising: a receiving computer including at least one processor and computer readable memory; a server computer including at least one processor and computer readable memory; program code for loading said document into said computer readable memory of said server computer, said document containing conventional tags and at least one custom tag, said custom tag associated with machine-executable instructions resident on said receiving computer, wherein said receiving computer is in communication with a network; program code for providing said document from said server computer to said receiving computer over said network; and program code for identifying said custom tag, wherein said identifying includes scanning a document object model (DOM) representation of said document in said receiving computer for the presence of said custom tag, and inserting, by a Web browser executing on said client computer and prior to rendering of said document on a display device, said machine-executable instructions into said document at a location associated with said custom tag, wherein said inserting includes modifying said DOM representation of said document to replace said custom tag with said machine-executable instructions, wherein said executable instructions are for rendering a tree control display.