You can mark your WordPress posts as “Private” in addition to “Public”, “Draft”, “Password Protected” and such. In 1.2 the private posts are not displayed on the blog, not even to the author of the private posts, when she’s logged in. So they are like drafts which do not show up as such. I beleive that the behaviour is the same with 1.5, with Private Posts disappearing down some crack, so the only place they are listed in in the admin section for managing posts. I have been thinking about making it so that the Private Posts are only visible to the author of the post, when she visits the blog.
I beleive some thought needs to go into why private posts are not displayed on the blog at all, and as to what their purpose in life might be, in 1.5 at least