Everystockphoto.com
"Everystockphoto.com is a search engine for freely licensed photos, and acts as a portal for stock photography. Everystockphoto.com is owned and operated by Vibrant Software" (from website).
"Everystockphoto.com is a license-specific photo search engine. Currently we index and search millions of freely licensed photos, from many sources, and present them in an integrated search. Everystockphoto.com searches photos under a number of free licenses. We display the license icon to the below and left of images, and clicking this will take you to the license page. Licenses include a variety of Creative Commons, GNU, public domain, and custom free licenses. We also list royalty-free photos from our partner Fotolia. Photos for sale have a dollar sign as a license icon" (everystockphoto, 2006-2010).