Updated December 2010: Site Blog Dashlet is now hosted on Share Extras.
This extension to Alfresco Share provides a custom Site Dashlet, which displays the most recent ten posts from the site blog component.

To install the dashlet download the ZIP file package the latest blog-dashlet.jar file from the Share Extras project and extract the contents into the tomcat directory of your Alfresco installation drop it into tomcat/shared/lib or WEB-INF/lib inside the Share webapp. The package will install the dashlet web script and a single CSS file.
Also pictured in the screenshot is the Site Tags Dashlet, which displays a tag cloud visualisation for all the tags within a site.