Today I’ve released a WordPress plugin called “Recently Updated Pages” which is a WordPress Widget that displays your recently updated page list on the sidebar.
I was looking for a similar plugin but after searching for a while I wanted to write my own plugin. I followed some instructions on couple of websites and created this plugin. It uses WP_Widget class from WordPress core and extends it to build the widget. You can download it form WordPress Plugin page at http://wordpress.org/extend/plugins/recently-updated-pages/
In case if you want to make a small donation you could do so at http://resource.bdwebwork.com/WordpressPlugins/RecentlyUpdatedPages/
UPDATE AS OF SEPTEMBER 17, 2009:
I’ve updated the plugin and committed the latest version (1.0.1) to WordPress plugin directory. The updated version will allow users to include list of blog Posts in the Recently Updated list. Originally the plugin only displayed list of updated Pages and now with this optional choice you can toggle between the option.