David Streitfeld wrote an article in the New York Times about the proliferation of fake online reviews. Researchers developed an algorithm to detect and limit the spread of fake reviewers. This sparked the interest of several top companies such as Amazon, Hilton, TripAdvisor and several specialist travel sites.
Click here to read the whole article.
http://www.nytimes.com/2011/08/20/technology/finding-fake-reviews-online.html