Barry Kooij

Never5

With this plugin you can add tags to pages like you can to posts by default. The plugin also adds a new widget to display the page tags.

Page Tag Cloud

This plugin allows you to add tags to pages and display them in a tag cloud widget.

tomi33

Allow pages to be given tags just as if they were posts.
This plugin is designed to easily allow you to display related posts on a page (by checking to see if they have matching tags), not to show the pages under the tag archives by default. (Although there is a setting for that)
The purpose of this is to easily allow the site editor to ‘relate’ pages to posts using a process they are familiar with.
<h3>Instructions</h3>
Once the plugin is enabled you will be able to add tags to pages without any further configuration

Tomi Page Tagging

Allow pages to be given tags just as if they were posts.

Page Tag Cloud vs Tomi Page Tagging