Before I had heard of Avantslash, I wrote a perl script that did essentially the same thing. Then I started using plucker, so I changed my script to output a bunch of handheld-friendly html files, and I would pluck those files. The current version is available
here if you'd like to give it a try. It requires perl and libxslt, both of which are available for windows, but I've only used it on linux.
I've also written an XSLT stylesheet for use with sunrise, which is how I currently read slashdot on my handheld. I've been meaning to post it to the sunrise forum here on mobileread, but since sunrise XP doesn't use stylesheets any more I didn't think there would be enough interest.