Eric Marden

A custom plugin that will display dynamic text from the values you enter in special custom fields on a post inside of a WordPress Widget.
Add any text you want as the value of the ‘posty’ custom field and it will show up in this widget. Title the widget with the ‘posty-title’ custom field. It only works on single posts.
<h3>License</h3>
The Posty Widget plugin was developed by Eric Marden, and is provided with out warranty under the GPLv2 License. More info and other plugins at: http://xentek.net
Copyright 2008 Eric Marden (email : wp@xentek.net)
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Posty Widget

A custom plugin that will display dynamic text from the values you enter in special custom fields on a post inside of a WordPress Widget.

Internet123

Control widget areas on a per-page / per-post basis.
Gives you the ability to show or hide individual widget areas on each page / post as well as completely substituting the widgets shown in a specific widget area on a specific page or post.
<h3>Compatibility</h3>
The plugin has not been tested below version 3.3.

Per Page Widgets

Control widget areas on a per-page / per-post basis.

Posty Widget vs Per Page Widgets