These datasets are separated from the rest of the benchmarks because they don't have published benchmark uses or solutions. These datasets are very large in nature.
Visualization Publication Data Collection 1990-2015 (and growing) VisPubData
US energy data from the Energy Information Administration
Census data from the US Census
Social Science research data from ICPSR (Inter-University consortium for political ans social research)
Household Travel Survey from the US Department of Transportation
Odum Institute provides collection of U.S. Census data, North Carolina State Data Center and the National Center of Health Statistics.
OECD (Organization for economic co-operation and development) includes data and metadata for OECD countries and selected non-member economies.
Statistical benchmark on the World Development Indicators 2009 that helps measure the progress of development from the World Bank
Variety of data on all UN contries from UNdata
Global and internationally comparable statistics on education, science, culture and communication from UNESCO
WHO | Data and statistics provides national statistics for 70 core indicators on mortality, morbidity, risk factors, service coverage, diseases and health systems.
Global terrorism database is an open-source database presenting information on terrorist events around the world since 1970.
Crime data includes crime statistics from Indianapolis.
Various datasets used in the DataExpo contest of the Graphics Section and the Computing Section of the Joint Statistical Meetings.
Google Public Data
Official boundaries of the United States, such as states, counties, etc
More free shapefile maps
Pete Warden, Data Source Handbook, O'Reilly Media
Congressional Data Index
NY Times Congressional Data
Data Sources for Social Scientists
San Francisco Data
District of Columbia Data Catalog
Statical information shared by European Union
The World Bank
Australian Government Data