morgueFile: The Public Image Archive

"A place to keep post production materials for use of reference, an inactive job file. This morgue file contains free high resolution digital stock photography for either corporate or public use. The term "morgue file" is popular in the newspaper business to describe the file that holds past issues flats. Although the term has been used by illustrators, comic book artist, designers and teachers as well. The purpose of this site is to provide free image reference material for use in all creative pursuits. This is the world wide web's morguefile."

It's an interesting concept: a place where photographers upload their images for use by others. You can use these images for pretty much anything, without giving credit, but you can't sell them. I spent a few minutes browsing through some of the images, and from what I saw, the quality of the images from isn't exactly impressive - I saw a lot of images that would quality as "snapshots". However, if you're looking for an image of something and don't want to pay for an image from iStockPhoto (or another commercial service), this might do the trick. And for being a site I've never heard of before, they have a good amount of photos - I typed in "sunset" as a search term and found 3937 images. Worth checking out is the Classroom area, which has some useful articles on photography.