After approximately two months of heavy development, we're ready to release the beta version of the StupidFilter. We've moved to a support vector machine algorithm and a much more sophisticated parser. The classifier itself is about 30,000 times faster than the alpha code and should reduce false positives significantly. The upshot is that we're now ready to start putting the filter to work! We expect to release a WordPress plugin in short order. In the meantime, please feel free to download and build the filter and start working on your own plugins and implementations.
Check the downloads section for the beta release.
Additionally, try out the live demo.