WordPress Admin Notepad is a plugin for wordpress 3.0+ that allows selected user group to view or edit notes as long as they are logged into admin panel.
WordPress Admin Notepad automatically creates a show/hide notepad toggle at top right corner (beside log out link) so that users can access their notes at anywhere.
WordPress Admin Notepad supports ONLY WordPress 3.0 and above, that is after wordpress added Roles & Capability.
What’s New
<ul>
<li>You can now configure the permission to view or edit the notes for the 4 user levels (editors, author, contributor and subscriber).</li>
<li>You can now save the state of notepad (visible or hidden)</li>
<li>Notepad now supports cyrilic texts</li>
</ul>
Features
<ul>
<li>Allows selected user groups (roles) to edit/view notes at anywhere in admin panel</li>
<li>The toggle at top right corner can be disable</li>
<li>Save the state of notepad (visible or hidden)</li>
<li>Configure the permission to view or edit the notes for the 4 user levels (editors, author, contributor and subscriber)</li>
<li>Size of notepad can be personalized (slim or normal) and will be saved using cookie</li>
</ul>
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WordPress Admin Notepad

Add a Notepad to your admin panel so that you can view or edit note at anywhere.

wycks

Like a built in notepad, leave notes for clients or yourself in the WordPress admin. Attach notes to above or below the editor of a post (or page or custom post type) and also has a default “Notes” section available from the admin menu which you can hide or show.
The style of the notes section has been updated with the changes in WordPress 3.8+. Please note that the UI will not look great on WordPress version lower then 3.8 and there are no plans to fix this.
Features :
<ul>
<li>Uses WordPress’s built in custom post types</li>
<li>Functions with default WYSIWYG editor</li>
<li>Uses WordPress’s meta fields if set to display on post edit screens</li>
<li>Shows “Notes” on one page in tab format (can be excluded)</li>
<li>Will not show in front end or search</li>
<li>Requires default post privileges</li>
</ul>
Notes :
<ul>
<li>It is currently only possible to set one note per post and one location (above or below editor)</li>
<li>Works with password protection in default section</li>
</ul>
Please report issues to: <a href="https://github.com/wycks/Simple-Admin-Notes" rel="nofollow ugc">https://github.com/wycks/Simple-Admin-Notes</a>

Simple Admin Notes

Adds a simple "Notes" section to the admin menu or posts

WordPress Admin Notepad vs Simple Admin Notes