Maximum posts per member
On a discussion mailing list, some people will occasionally write the majority of the email messages, thereby stifling the conversation, and keeping other people from feeling
comfortable posting their messages. Also, some people may write several small messages, when it would be better if they had combined their thoughts into one message.
For these reason, you may want to impose a "maximum posts per member, per day" limit. If a member goes over this limit, they must wait until the next day to post another message.