ActiveX is dead, don't even think about wasting time on proprietary tech that only works with 20% of my site's market share! The plugins will (if they even support file uploads) have very similar functionality but
now you're talking third party items that may or may not be installed in the browser that they are using.
A couple links that should help you get moving in the right direction...
MDN: https://developer.mozilla.org/en-US/doc ... plications
I made a multiple-image uploader that included thumbnail images of the selected images and accurate upload percentage indicators to show the progress of uploads. I'm not sure if you can get the text from a text file offhand though to me it would be similar if simply text instead of binary data. You're just going to have to do the research.