GeoMonitor

https://github.com/geoblacklight/geomonitor

GeoMonitor is a Ruby on Rails application used to monitor geowebservices. It was built out of the premise that users who are looking for and find data, should actually be able to access and use it.

The application is setup to periodically monitor WMS web services and log data on a layers availability.

You can see GeoMonitor in action here: http://geomonitor.stanford.edu

Or grab the source code on Github