I was getting 3k uniques from hijacking someones image on accident. It ranked number 1 when you searched for this person. I hotlinked the image on my site. In google's search the site I linked from was listed as the url but it was sending it to my site. It lasted for a few weeks. I see hijacked images all the time. If you look at the url for the image it will list 2 sites a lot of times. Here is an example. This site Techwoo.c0m (sorry if it is yours) hijacks images and gets most of it's traffic from it. This is the hijacked picture link that has the number one result for Gina Carano.

hxxp://www.google.com/imgres?imgurl=http://ginacaranomaxim.files.wordpress.com/2008/08/gina-carano-3.jpg&imgrefurl=http://techwoo.com/gina-carano-has-a-pretty-hairstyle/&h=500&w=333&sz=125&tbnid=t2d1mTcjxdUxCM:&tbnh=130 &tbnw=87&prev=/images%3Fq%3DGina%2BCarano&hl=en&usg=__3eH8An0Cl5Q 7GsBiosDX0Ebu8TU=&ei=z0O1Su3kJpOsMLnukNoO&sa=X&oi= image_result&resnum=4&ct=image

Looks like it uses the site that is hosting the image's PR but when you hotlink it all the traffic gets sent to your site instead. I've been trying to figure this out for months now after I did it by accident. I had the original sites url in my ALT tag but I think google changed something. All of my images were dropped from google search but it might have been because I was getting 3k hits a day on a blog that was up for less than a month. I'm not sure on how to get it back. Any advice would rock.