Wondering whether your image is re-produced somewhere else in the web without your permission? OR Wondering whether the image you are seeing appears anywhere else on the web? Well in both cases you have to use Google Image search or manually visit web pages which again is a tough ask. The solution to this is TinEye, a reverse image search engine with over 1 billion images in its index (and growing). TinEye is in beta and was created by Idée Inc.
Check out this video to understand how this reverse image search engine actually works:
To learn more about how TinEye works, benefits of using this web app, etc. please check its FAQ section.
There are various ways you may use TinEye. It can be a Firefox/IE plugin, a bookmarklet (which can analyze all the images inside a web page). You may also upload an image or use the image URL to check. Please check its plugin page for more details.
So next time before using copyrighted images think twice 
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Its nice to find to the duplicate Image on net. It will help to reduce the fraudness type of cases.