GeoRSS

This site describes a number of ways to encode location in RSS feeds. As RSS becomes more and more prevalent as a way to publish and share information, it becomes increasingly important that location is described in an interoperable manner so that applications can request, aggregate, share and map geographically tagged feeds.

To avoid the fragmentation of language that has occurred in RSS and other Web information encoding efforts, we have created this site to promote a relatively small number of encodings that meet the needs of a wide range of communities. By building these encodings on a common information model, we hope to promote interoperability and "upwards-compatibility" across encodings.

from the infosthetics blog - "semantically ordered tag clouds that resemble self-organizing maps. the size of the text & the color brightness of the background represent the frequency of the different terms. this technique has been applied to visualize the keywords present in website favorites, or the tags used by different del.ico.us users for the same web pages."

 tags clouds developed by Moritz Stefaner

Allows users to store, tag, and share locations -- based on google maps, but does interesting things. Users add photos of places, and lots of other tagged info about the places.