From http://banbuilder.com/:
Why BanBuilder?
BanBuilder is designed to allow you to customize your banned-words list, and is constantly evolving. As people find new ways around the banned words (using symbols instead of letters, for example), they get added to the database. And its all free!
The idea sounds great, but some people have added some words which probably shouldn't be banned, e.g. "unwed" probably isn't a swear word, nor one worth banning. Certainly banning "screw" from a DIY site isn't going to helpful either.
Can something like this be useful, given the wide range possible opinions people have?