I have no idea what practical use this application might have, but TagGalaxy allows you to use tags from Flickr to create an entire world of photos. I used the photos from our collective PhotoFridays project (launched by Bonnie to great success) and, although there are not quite enough photos there yet to cover the entire TagCloud world, it was still pretty neat.
I used screenshots to capture the PhotoFridays TagCloud because I can’t find the way you might embed the actual world into a blog. But you can do it yourself. Just go to TagGalaxy, write in the tag “photofridays” into the prompt and give the world a spin. I think it will be cool to come back and do it again later this summer, when the pool of pictures gets larger.