How do you implement a good profanity filter?

Question

Many of us need to deal with user input, search queries, and situations where the input text can potentially contain profanity or undesirable language. Oftentimes this needs

Answer 1

I concluded, in order to create a good profanity filter we need 3 main components, or at least it is what I am going to do. These they are:

1. The filter: a background service that verify against a blacklist, dictionary or something like that.
2. Not allow anonymous account
3. Report abuse

A bonus, it will be to reward somehow those who contribute with accurate abuse reporters and punish the offender, e.g. suspend their accounts.