Wikipedia
StupidFilter is an open source software project currently in development. Its goal is to give content websites, such as blogs and forums, the ability to block "stupid" user comments, i.e. contributions that fall below a certain threshold of grammar and intelligibility. For instance, a message composed entirely of common chat room abbreviations like ur and lol would be considered stupid and thus blocked.
The algorithm behind StupidFilter is similar to that of Bayesian spam filtering technology. It is an adaptive filter that examines large amounts of sample unacceptable text, then scans for similar patterns in incoming comments. Most of the sample data was taken from comments on YouTube. The StupidFilter project is led by Gabriel Ortiz and Paul Starr. Its beta release was made July 22, 2008.