Tracking down your images

For anyone who puts images online, say, for a lecture, but is a little wary of it getting out into the bigger world here's a neat thing. Tinyeye scans images for the similarity even if they've cropped, photoshopped, turned into black and white, you name it. Plagiarists beware.
Of course, if you put up anatomy material online and really want to protect it from being released onto the internet, you could use it to make sure it hasn't already.