For hundreds of thousands of people, the dream of making an Internet fortune works like this: Earn pennies at a time in exchange for allowing Google Inc. or Yahoo Inc. to place advertisements on a personal or small-business Web page.

http://www.msnbc.msn.com/id/14067219/

[ via http://plentyoffish.wordpress.com/2006/07/28/washington-post-on-people-making-truckloads-from-adsense/] (he makes almost 1 mio with adsense in 2 months)