TinEye – Reverse Image search engine
Came across TinEye; a ‘reverse image search engine’ today. 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. It is free to use for non-commercial searching.
TinEye regularly crawls the web for new images, and they also accept contributions of complete online image collections. At the time of writing this, TinEye has indexed 1,572,822,693 images from the web to help you find what you’re looking for.
There are also a number of extensions available for the main web browsers, as well as a mature, paid-for API (designed for commercial searches etc). It is definately one to watch!