Why you should never write P0rn and other s3xual words out.

Many people use Qstodio and K9. (I recommend using both at the same time)
Both are free, by the way. Back to topic: Many use these filters and threads which's titles or content contain words like P0rn, S3x and the like may be filtered by the blockers rendering them left unread by many/some users. It's better to use abbrevations or other letters.

Cheers