Over the last decade, I have had a lot of lessons about the value of good data. Some good…some not so good. If you like good data, you should find this modest list very helpful.
GeoCommons: GeoCommons is the public community of GeoIQ users who are building an open repository of data and maps for the world.
OpenStreetMap: A free worldwide map with user populated content and data. The data is free to download and use under its open license.
TIGER: A free to use database provided by the US Census Bureau containing an extensive amount of population and geographic data.
Global Health Data
Global Health Facts: Self run studies on global health.
World Health Organization: As the directing and coordinating authority for health within the United Nations, the organization maintains broad statistical studies on the state of health throughout the world.
OECO Statistics: Organization for Economic Co-operation and Development maintains broad study data over a wide variety of topics.
Government and Politics
Census Bureau: Maintains several databases that are used to inform policy decisions within the United States. The data covers broad to specific population characteristics.
Data.gov: Maintains broad United States government data
Follow the Money: An interesting database covering campaign contributions within the United States.
DBpedia: A crowd-sourced community effort to extract structured information from Wikipedia and make this information available on the Web.
Alexa: This is a site tracking service owned by Amazon.com. It consists of a database that allows you to look up visit statistics for websites across the world.
Way Back Machine: This site lets you look at websites over time. You can choose a site and discover what it looked like a day, a week, a year or several years ago.