Limit posts by certain members?

Is there a way to put a cap on just a member, or perhaps 2 who come in with just totally off-the-wall posts, who just keep posting off-topic stuff and drive other members nuts?
We don't want to ban, just "curb his enthusiasm" a bit. Post-after-post.....
Say, put a max post limit per day on him - but not others?
Some post a lot of really good stuff, and we don't want to limit them in any way......... but we have one or two......