Mapping social networks is not a new concept, but this image is worth a quick look. It shows the origin of tweets and presents them as heat map but uses intensity to represent clusters. The effect is that it looks very similar to a “Night Sky” image but no background image has been used. It does appear to pick out the main centres of population quite well. You can browse more of Eric Fischer’s maps on his Flickr page. You can read the original Weird UK article here.