The Africa Map project, currently in beta, is an online map and data viewer created by Harvard University. The map combines data sets of numerous categories from a wide variety of sources, allowing thematic maps to be viewed and explored. The purposes of the project, according to the project web site:
Interact with the best available public data for Africa
See the whole of Africa yet also zoom in to particular places
Accumulate both contemporary and historical data supplied by researchers and make it permanently accessible online
Work collaboratively across disciplines and organizations with spatial information about Africa in an online environment
This is a very useful interface allowing visitors to visualize all U.S. records of cancer deaths over a 50-year period. Epidemiologists and others can drill down to the county level, selecting from dozens of different types of cancer. Data can be output in a variety of formats, including static image for copying and interactive Flash maps.
"This program is intended to make working with the Generic Mapping Tools (GMT) easier. iGMT provides a graphical user interface for GMT and is written in the Tcl/Tk computer language. Besides supplying a user friendly way of handling GMT, iGMT comes with built-in support for many different geoscientific data sets, such as topography, gravity, seafloor age, hypocenter catalogs, plate boundary files, hotspot lists, CMT solutions etc."
An interactive mapping tool with a built in datasets.