Morguefile: Public image archives for download. For creatives by creatives
Wikimedia Commons: A database of 11,469,650freely usable media files to which anyone can contribute.
Pics4Learning.com: A safe, free image library for education. Teachers and students can use the copyright-friendly photos and images for classrooms, multimedia projects, web sites, videos, portfolios, or any other project in an educational setting.
Flickr: Share your life in photos. Upload photos to share with friends.