Amerika writes "Craigslist is 'the single largest source of prostitution in the nation,' according to Cook County, Illinois Sheriff Thomas Dart. He has announced that he's filing a lawsuit against the popular classifieds site. Craigslist says it's determined to prevent criminal activity." NewYorkCountryLawyer adds a link to the 28-page complaint (PDF), which "alleges that Craigslist maintains 21 classifications of sex-for-hire, coded as 'w4m,' 'm4m,' 'm4w,' etc." and that it has facilitated child prostitution and kidnapping and human trafficking.