Now you too can bring your own datasets to Google’s correlation service, “Google Correlate” – read about it here:
http://googleblog.blogspot.com/2011/05/mining-patterns-in-search-data-with.html
This is a continuation of the Google Flu Trends -thing which started when Google search data was found to correlate with flu activity. Simply put: when people search for flu-related stuff on Google’s search engine more than usual it indicates a peak of flu activity. Now you can test your own findings and see if you stumble on any interesting phenomena out there in the world… there’s bound to be lots of interesting stuff to test, like… er… wait for it… ah, eventually something will crop up – but just remember: correlation does not imply causation! [wikipedia.org]