Wiki Mapping

The Google Maps API and the KML mapping file format has opened up new ways of manipulating data geographically. The application of geocoding to wikis and other publicly modifiable information banks like Wikipedia open up new avenues of visualizing the world. Recent examples include the new Wikipedia links in Google Maps, which displays links to wikipedia articles in their geographic location. Continuing the tradition of the Wiki, users will be able to contribute their own geographic locations and corresponding articles. This space will be dedicated to examining emerging mashup “Wiki mapping” applications and their potential uses in education.

Google Spreadsheet Mapper

Published by Google itself, the spreadsheet mapper tool is a template that provides the framework for creating Google map way points with pop up bubbles.
Also has the ability to organize way points based on a timecode.

Panoramio

Another Google production, Panoramio integrates geotagged photos with Google Maps.

Map Channels

A website dedicated to adding custom user data and photos to Google Maps.

Tagzania

A website where users can make wiki-like contributions to their own and others maps.

Batch Geocoder

Accepts spreadsheet data: zipcode, standard U.S. Addresses and outputs latitude and longitude coordinates.