MapQuest - http://www.mapquest.com/
Find directions for and explore towns and cities worldwide. Display addresses on a map, view nearby businesses, get driving directions and maps, and plan a trip with city information. Also includes aerial photographs of selected areas.

National Geographic Map Machine - http://plasma.nationalgeographic.com/mapmachine/
Dynamic maps in a variety of formats.

MSN Maps & Directions - http://mappoint.msn.com/
Online street maps and driving direction generators for the U.S., Canada, and Western Europe, as well as static reference maps at the continental level.

Multimap - http://www.multimap.com
Maps of UK at 1/10000 including OS Landranger, other countries varying down to 1/200000.

United Nations: Cartographic Section - http://www.un.org/Depts/Cartographic/english/htmain.htm
General country and special issues maps.

Map Machine - http://www.nationalgeographic.com/maps/
Access to political and physical maps and information for anywhere in the world by the National Geographic Society.

Atlapedia Online - http://www.atlapedia.com/
Contains full color physical and political maps as well as key facts and statistics on countries of the world.

MSN Learning & Research - Maps Center - http://encarta.msn.com/encnet/features/mapcenter/map.aspx
Zoomable maps of all countries.

Rand McNally - http://www.randmcnally.com/
Online maps, driving directions, and travel store.

Quick Maps of the World - http://www.theodora.com/maps/
Small GIF maps of the countries of the world.

Expedia Maps - http://maps.expedia.com/
United States road maps by address, and driving directions and maps of the world.

Green Map System - http://www.greenmap.com/index.html
Chart the ecologically significant places in cities around the globe.

TerraFly - http://www.terrafly.com
Aerial photography of the United States, searchable by place name or geographic coordinates.

Maps.com - http://www.maps.com/explore/atlas/
Downloadable digital maps, paper maps, travel accessories and atlases.

Worldwide Country Maps - http://www.weatherhub.com/maps.htm
Map for all countries in the world.

Atlas of the Biosphere - http://www.sage.wisc.edu/atlas/
A collection of maps, schematics, and information about human-environment interactions, directed at the education community.

Graphic Maps - http://www.graphicmaps.com/aatlas/world.htm
Has overview maps of each continent, and country-level maps.

World Atlas - http://www.sitesatlas.com/Atlas/PolAtlas/polatlas.htm
A complete atlas of the world featuring several thousand place names and colorful, accurate maps.

Excite Maps - http://www1.excite.com/home/info/maps/maps_overview/
Map a world address or get driving directions.

Cornell's Digital Earth - http://atlas.geo.cornell.edu/webmap/
Use this interactive atlas to create maps displaying land, oceans, borders, roads, lakes, rivers, roads, railroads, faults, mines, seismicity, and other geological, geographical, and geophysical data.

Great Circle Calculator - http://www.gb3pi.org.uk/great.html
A useful site for calculating direct line distances between any two points on the globe.

Map Maker - http://www.interromap.com/im_portal/interromap/map_maker/
Generates maps from latitude and longitude inputs.