I think the members of this forum are good enough people to police themselves and know what is appropriate for certain situations. I'm sure I've dropped an f-bomb on here before, but I only do it if I'm extremely enraged by ignorance or in response to a shot taken at me or my car. I don't think a profanity filter is necessary. If someone's angry, there's too many 4 letter words that they can use in any given situation and it makes understanding them more difficult. Instead, you should make a punctuation filter that limits people's posting capability if they don't use proper punctuation.