If you post photos to Flickr, you can set the license on your photos to the Creative Commons Attribution-No Derivative Works license.
This means that people can use your photos, but they must credit you when they use the photo. It also means they cannot alter the photo and redistribute it.
I have seen people get some great links from their Flickr pages this way.
Does anyone here at NetBuilders have a Flickr page? What license do you use on your photos?