A few comments on Digimarc. Unlike Larry F, the watermark has always worked for me. However, it has also always been relatively easy to remove the watermark, sometimes with very little manipulation, and it doesn't seem to matter what embedding strength was used. It has always survived merely being transformed from one image format to another or copying. Robustness seems to vary from image to image so individual image experimentation is in order. If you want absolute protection via identification I do not think digital watermarks are secure enough. Their greatest value seems to be the ease with which interested viewers may determine and contact the image's author. If you are a working artist this certainly justifies its use. But this whole issue begs the question "How many of us actually produce anything worth protecting?" If someone likes your picture & keeps a copy for themselves or as screen wallpaper is that such a terrible thing? Unless someone is trying to make money off your work I don't think protection is much of an issue. If the image is not rather popular it is unlikely that such commercial thefts will be profitable. And if the work is popular, its very notoriety is usually sufficient to give protection. From time to time some of my stuff has appeared on others' sites. I only knew because someone else sent me an email to tell me. In each case it was a vanity thing in the sense that the thief was not trying to make money but simply presenting the work as their own. A simple email thanking the thief for their interest & requesting a web link solved the problem. But either way, this is not something that would cause me to lose sleep. Image thieves will always be image thieves whereas I can always create something new. Sometimes I think concern over image protection is either misplaced ego or paranoia. I'd rather spend my thought on my next image.