Google has a number of applications, such as Google Docs, that are being put to creative and innovative uses. In the field of public health, for instance, Google Flu Trends uses aggregated search data, combined with IP addresses, to track flu outbreaks.
They claim that there is a strong correlation between searching and disease outbreak (although they do recognize that not everyone who searches for “flu symptoms” might be sick – you might, for example, just be writing a paper for your ESM class), and that their data can indicate an outbreak as soon as two weeks before the CDC or another indicator system. (The CDC relies largely on doctor reports that are aggregated by the CDC and state health departments.) Another benefit is the near-instant reporting of results, allowing researchers to see what is happening right now.
A Flash-based map of the U.S. allows you to view flu trends for this year, broken down by state. As a researcher, you can download their raw data in a CSV-format. The FAQ for the Google Flu Trends answers questions about flu statistics in general and Google Trends in particular, including privacy questions related to this service.