Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.
Alex Suhre just posted to the Oracle ECM Forum a link to a JavaScript based HDA data parser that allows you to paste HDA formatted data into a box and get a more human readable view of that data. It looks nice, and I have tried a few pieces of data in there and it worked well. I have not put it through the paces to see how it handles odd data or characters. It looks like you can download it as well, although you have to supply some information to be able to do so.
Real world applications? Well...not sure just yet, but it is neat, and it is always nice when a tool is turned over for community use.