1. – Easy way to access/download 2000 and 2010 Census data.
  2. – Free vector and raster map data at 1:10m, 1:50m, and 1:110m scales.
  3. – A portal for high-resolution topography data and tools. (Especially for LiDAR)
  4. – Armed Conflict Location and Event Data Project.
  5. – Global Database of Events, Language, and Tone (GDELT). Lots of data from 1979 to present.