Wikipedia
Geo-Wiki
Geo-wiki is a platform for engaging citizens in environmental monitoring. It aids in both the validation of existing geographical information and the collection of new geographical information through crowdsourcing. Using tools such as Google Earth, Bing Maps, Geotagged photographs and the internet, individual volunteers are able to contribute valuable information. It provides feedback on existing information overlaid on satellite imagery or by contributing entirely new data. Data can be input via the traditional desktop platform or mobile devices, with campaigns and games used to incentivize input. Resulting data are available without restriction.