Flickr is a social photo and video sharing web site where users submit photos for public display. Many Flickr users make their photos available for non-commercial use through a create-commons copyright, giving students a great database for accessing photos for use in projects and reports. Flickr has users from around the world, who upload and share new photos throughout each day. Photos are easily located on the Flickr web site by searching keywords that will be matched to the titles and tags that photographers attach to their photos. In addition to accessing the photos, students can also communicate with the photographers through the site's comment tool.   Flickr is a great resource for locating first-hand images and communicating with people from around the world. 

Flickr Commons
http://www.flickr.com/commons/