The YUI Uploader Control provides file upload functionality that goes beyond the basic browser-based methods, including integral support for multiple-file upload and progress tracking.
Simple Uploader Example With Button UI: A demonstration of core features of the Uploader Control. In this example, the Uploader control is rendered as a sprite-skinned button. The user is allowed to select a single file and upload it to a specified location. The upload progress is tracked and reported back to the user.