Taggalaxy is one of many online tools that that is a search engine for Flickr. ( Flickr is a photo sharing site powered by Yahoo! that allows users to upload and share their photos.
http://taggalaxy.de/
The way it works is that you type in your key word e.g. Egypt and Taggalaxy finds all of the photos on Flickr which has that key word in its Tags and then presentsthem all as planets which you can manipulate with the mouse. Click on a planet to zoom in.
Taggalaxy, among other things could be used as a stimulus for creative writing or class discussion.
As with all resources on the internet, it is vital that you check before showing your class. Taggalaxy randomly chooses photographs. You need to make sure that these photos are suitable for your pupils.
Other online tools based on flickr include: Flickrcc,(search Flickr) PhotoSoup (wordsearch), Bubblr (create a comic strip from the photos) and 10 by 10 (photos in the news).
Most schools use clipart for presentations on their interactive whiteboards. Schools should now be considering using photos that are in the public domain or licensed under a creative commons license and making sure, of course, attribution is given to the author. For creative common searches on flickr try http://flickr.com/creativecommons.