So, I had a need for an easy-to-use hex firmware uploader that anyone could use, without having to explain how to install and run the IDE, or explain the command-line for avrdude.
It's actually pretty easy to just use avrdude, but sometimes we have people who aren't even familiar with the command shell in windows, mac, or linux. Considering this took all of a few hours to put together, it costs less to do than constantly re-explain avrdude grin
I'm sharing it in case anyone else has a need for similar, it only works with the Atmega328-based duemilanove's, afaik, but can easily be modded to support any board.
I use it with avrdude 5.10, so there's no need to do any serial port reset hackery, instead it uses the "arduino" programmer type.
Here's the processing source and a windows binary: http://dynamicperception.com/docs/mx2/uploader