viewurpmi is a set of scripts that generates a webpage listing of all required updates for a group of Mandrakelinux boxes. It was originally created for the CanOpenER cluster of servers.
This version will just use a cronjob against 'urpmq' on each box to generate a list of RPMs that require updates.
viewurpmi requires an 'authorized ssh-key' to be setup on each host you want to monitor, so that it can run the required commands
It's not very elaborate, but it gives you an 'at a glance' overview of several boxes, and I found it useful for myself, so I packaged it up for all to enjoy :)
View screenshots and download it from http://www.warpedsystems.sk.ca/staticpages/index.php/viewurpmi