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.

Iftekhar Bhuiyan

AdminPad allows WP site admin (only) to write down simple note from WP dashboard using simple widget. Deleting this plugin will also delete data saved by this plugin on your database.
Features: 
* Light weight plugin. 
* Simple user interface.

AdminPad

AdminPad is a simple note taker for WP site administrator only.

WordPress Admin Notepad vs AdminPad