A lot of business is done on the Internet, but the model for making money there isn’t as straightforward as “sell a thing, make a profit.” So how do the web services you use every day make money? The aptly named “How Do They Make Money” has some answers.
More:
http://gizmodo.com/5945562/how-to-find-out-if-the-web-services-you-use-every-day-are-profitable
