One must be allowed to switch off HTML filtering altogether if desired. Entering a list of all HTML tags is ridiculous and error-prone. Some legitimate tags will always be omitted, frustrating expert users.
Preformatted option is a disaster because a lot of users will pick it when they shouldn't. It has been available for some time on this board and it mainly resulted in fixed-width postings appearing at random. If somebody doesn't know how to use <pre> tag and < > stuff, he shouldn't be posting code anyway.
