1. A computer system comprising: computer-readable media, a reader program for rendering information in a computer-readable document file in human-cognizable form, said reader program being stored on said computer-readable media, said reader program including a document parser for identifying a network location specified by an original version of said document file, a network interface for accessing an updated version of said document file via said network location, and a renderer for causing information in said updated version to be rendered in human-cognizable form.