Check it out! You can blur images dynamically using only Actionscript. This can be useful for pause screens or image gallery interfaces (to name just two of the uses). It's surprisingly easy to do. Tutorial follows. Download the source at the bottom.
I've been working on a little app that lets me download large files from my Dropbox account using Adobe Air. Essentially, I needed a way to download 700+ MB files without them going entirely into memory first (I want this app to run on any device). So that rules out URLLoader.
Basically, I needed a way of progressively downloading the file, and offloading it onto the hard disk to clear up memory for the next bytes of the download.