Cool "reverse image search engine"

Hi all,
 
While I was researching for my final post I found a reference to this site: http://www.tineye.com/

Here's the description: 
TinEye is a reverse image search engine. It finds out where an image came from, how it is being used, if modified versions of the image exist, or if there is a higher resolution version.

I thought it was worth sharing.

Happy Thanksgiving.
 
Amy