Add notes on the “edit post” and “edit page” screens’ sidebars in WordPress 2.8 and up. When used with Peter’s Collaboration E-mails 1.2 and up, the notes are sent along with the e-mails in the collaboration workflow. There is also a general and private notes system on the dashboard.
On its own, this plugin adds a panel to the sidebar of the add and edit post / page screens so that users can add notes for themselves or others and keep track of these notes. Whenever you save a post, you can type a note to be displayed along with the post in the edit view.
On the dashboard, there’s also a summary of the most recent notes. By default this shows notes by all people on relevant posts / pages. There is also a general and private notes system.
For an illustrated explanation on how the plugin works with Peter’s Collaboration E-mails to send e-mails with the notes, see this page.