Amazon S3 Upload facility within Expression Engine

I have an Expression Engine site that gives members the facility to submit some files and some information about the files. I need to create a form that allows the member to do the following: • Upload 3 files to Amazon S3 (up to 100mb) • See a progress bar of the uploads • See a small confirmation success icon when each file has uploaded • Disable the ability to progress to the next stage until all 3 files have uploaded The form must work across all modern browsers, on both Mac and PC. Fitting this in with the Expression Engine site would be ideal, if however you're not familiar with Expression Engine, then developing the form with PHP would be ok.