How can a simple virus bring down Google, Microsoft, and yahoo?s ad revenue

I was just wondering how Google, Yahoo and Microsoft make money for the clicks made on ads. In the process I found a serious vulnerability which can make huge loss to the site owner and also to these big companies. Well this might be already thought by someone else, but as I searched (used all these above mentioned search engines) I didn?t find similar thing mentioned else where, hence thought of putting down it myself.

do read more at http://sureshkaukuntly.blogspot.com/2007/05/how-can-simple-virus-bring-down-google.html