Trendsmap has done a well design to display local information posted to Twitter. This feature of local information becomes possible by the Geotagging API of Twitter, which has become publicly available lately.
Trendsmap displays the Tweets on a world map. Local information becomes available by zooming the map, tabs for cities and regions (upper left) as well as by a search engine. If a location has been choosen, the local tweets are streamed into a particular frame. Too, a choosen map may become embedded into other sites (s. upper right).