Ushahidi is an open source real time crowdsourcing tool that maps crisis incidents sent in through mobile phones. Like wordpress or tumblr, Ushadhidi is a platform. You can embed a map into your website or create your own separate version.

Crisis mapping utilizes mobile technology, geospatial platforms, visual models, and statistics to spur rapid early warning responses in a range of disaster scenarios. As a tool, crisis mapping has enabled those on the ground to better plan and allocate resources in humanitarian emergencies.

Essentially, crisis mappers are engaged in the live mapping of evolving catastrophes. Interestingly, crisis mapping technology has been leveraged in numerous cases including political, social, and environmental crises.

Founded in 2009, the International Network of Crisis Mappers remains the world's largest and most active association of crisis mapping community members.

http://crisismappers.net/

http://irevolution.net/2011/01/20/what-is-crisis-mapping/

Worldmapper is a collection of maps that are resized according to a particular subject. This provides a very starting visual method of appreciating the way that we use our resources, or emit pollution, or receive more or less income.