I'm not sure what Mohamed was referring to specificially, but you may want to take a look at:
- http://www.managingnews.com/
- http://tattlerapp.com/
- http://www.cyberwatcher.com/ (not free or open source)
There are many others in the vein of those listed above. Not sure about 'off-the-shelf' source / fact checking tools -- would be great to know if they exist.
Phillip.