UN Cartography Section Maps
CIA maps | CIA Factbook
National Park Maps
USGS The National Map

Natural Earth
Census TIGER/Line Shapefiles
DIVA-GIS | Country Boundary shapefiles | GADM Country/World shapefiles
30-Meter SRTM Tile Downloader
NOAA Digital Terrain Data

NJ Health Statistics from the Dept. of Health
NJ Economic Data from the Dept. of Labor
NJ Geographic Information network
NJ Dept of Transportation Maps | GIS data
NJ Geological Survey Geodata
NJ DEP Open Data
Environmental Protection Agency in NJ

Geo for All free geospatial education
Open Street Maps
Discover QGIS | download
Inkscape (vector drawing & editing)
Open Street Maps
Daylight Map Distribution 
Map Warper georectifier, and image georeferencer tool

Social Explorer demographic data for the US
SEDAC CIESIN socio-economic maps & data
IPUMS worldwide census data to study change
FAO GeoNetwork - International Geospatial Data

Perry Castenada Map Library
Acme Mapper Google interface with various map overlays