I have written a plugin for the continuous integration server Hudson which uses a metric-fu rake task at its core to build and present graphs representing different metrics over successful builds. It currently supports:

The source is available on Github:
http://github.com/josephwilk/rubymetricfu
Installing
Currently all Hudson’s plugins are stored in something called SVN. Being more of a GIT myself you have to manually install the plugin rather than using the automatic Hudon GUI install method.
Install steps:
Follow the metric-fu installation guide (http://metric-fu.rubyforge.org/)
Ensure project code has a metrics:all rake task (auto added when you require metric-fu)
Download the rubymetricfu.hpi plugin file
Copy the file into your plugins folder within you Hudson install. Hudson’s default is ~/.hudson/plugins
Restart hudson
Go to the ‘configure’ link for a project and select the Ruby Metric-fu report option (see below)
(Optionally) Pick which Rake version you want to use.
