The design and display of information is not new but the Flickr Related Tag Browser lets you surf Flickr's 'tag space'. Flickr tags are user generated keywords used to classify images. When you type in a tag, each tag has a list of 'related' tags, based on clustered usage analysis.
Check out how AirTight has adapted the Flickr API.
Check it out at http://www.airtightinteractive.com/projects/related_tag_browser/app/
