You give TinEye an image by either uploading it or providing its URL on the web. TinEye searches the web for images that highly match the image you have provided in terms of pixels and gives you results in descending order of their relevancy.
Basically it helps you find image duplicates on the web by providing you location of each and every copy of image found. Alternatively, TinEye can be used to find high quality versions of a specific image. The great thing is that it also detects and displays image alterations in the search results. For example I used TinEye to search the web for the Mona Lisa image on the right.
Surprisingly, TinEye even found altered forms of the Mona Lisa image and displayed them in the search results.
TinEye is currently in a Private Beta and has indexed over 500,000,000 images. It even has a Firefox plugin which makes searching for images on the web as easy as a pie. Below you can see a live video demo of TinEye:
Free TinEye Invites
IDEE is giving free TinEye invites to some Sizlopedia readers so if you want to get your invite, just tell me why do you think TinEye will stand out among all other image search engines in the comments below.
I will hand-select some of the best comments and they can go image-hunting right away!