Afriterra Foundation provides historical maps of Africa
American Geographical Society Library (AGSL) Digital Map Collection contains over 500 maps from the 15th to the 20th century.
Global Poverty Mapping Project, of the Center for International Earth Science Information Network. The website also provides subnational data sets with a catalog describing variables available in each set and papers and presentations by CIESIN and collaborators during the project period.
Harvard Geospatial Library (HGL) has open access GIS "layers" available for download and provided "in a consistent, open format so they can easily be used by many different software packages without the need for translation."
Massachusetts Historical Society online maps include twenty-four manuscript maps of local towns and counties dating from 1637-1809 and eight iconic printed maps of Massachusetts and Boston.
For local maps, the Boston Redevelopment Authority webpage has maps and aerial photographs.
The World Bank Mapped is a mash-up of Google Maps and World Bank data, a visual look at wealth--and poverty--distribution throughout the world. Business Planet: Mapping the Business Environment is another interactive map and data mash-up providing information about doing business in various regions, such as Sub-Saharan Africa, or within a specific country. There are over 180 countries listed in this resource.
More statistical sources:
Boston Redevelopment Authority for City of Boston geographic, development and demographic information.
Historical Census Browser (University of Virginia) provides selected census data from 1790-1970. By state and county. Users may select geographic and demographic variables to create customized tables with sorting features.
U.S. Census Bureau, a resource for U.S. statistics.
Population Reference Bureau (PRB) "informs people around the world about population, health, and the environment, and empowers them to use that information to advance the well-being of current and future generations." Use the DataFinder to browse for data geographically and by topic.
Social Science Statistics, a subject page compiled by the Social Sciences Librarians on a variety of statistical topics: