Maps

GeoGraphics
Provides custom maps, drawings, and technical illustrations. Provides links to publications and images.
http://www.btinternet.com/~simon_tapper/index.html

Geologic Data Systems
Works with petroleum companies to make precise geological maps.
http://www.geologicdata.com

Geology of Greenland Map Series
Geological survey of Denmark and Greenland. All maps are compiled on CD.
http://www.geus.dk/departments/geol-mapping/map-cd-rom/gr-map-cd-rom-uk.htm

USGS NAWQA Digital Maps
National Water-Quality Assessment provides digital maps for a variety of themes.
http://water.usgs.gov/nawqa/digmap.html