Changing the referring string in the Browser User Agent

[whipnet]

I am not sure how to ask this question, but I have noticed in my webserver logs that under the referring url's, I will see one that has sent many hits, but when I go to that page, there is no reference to my site or images.

In a bizarre way, I think this is some form of marketing to get me to follow the link back and view the intended site.

The user agent of this person's browser has obviously been modified to show his site as the referrer whenever he visits any sites.

My question is out of curiosity, but how do you do it, and why?

Any help would be greatly appreciated.

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