Image Search Engine

http://tineye.com/

TinEye is a reverse image search engine. You can submit an image to TinEye to find out where it came from, how it is being used, if modified versions of the image exist, or to find higher resolution versions. TinEye is the first image search engine on the web to use image identification technology rather than keywords, metadata or watermarks. For some real TinEye search examples, check out our Cool Searches page.

Now you can do alot more with those picture you receive from email if you know what I mean XD..