Me and the Roads
Java game involving road-building.
http://www.kurumi.com/roads/matr/

Ratetheroads.com
A guide for conditions of facilities as rated by website visitors.
http://www.ratetheroads.com/

SABRE Photo Gallery
Contains examples from multiple continents, notably of Great Britain and Ireland.
http://www.sabre-roads.org.uk/gallery/

Trans Global Highway
Proposal by a private citizen to construct a global railroad and vehicle highway around the world including a tunnel under the Bering Strait from the United States to Russia, from Sakhalin in Russia to Hokkaido in Japan, and from Spain to Africa. Includes maps.
http://www.didik.com/highway/

Worldwide Highway Library
Covers North America (primarily the Western U.S.), Asia and western Europe.
http://worldwide-hwys.calrog.com

WRX900
Covers road trips in the United States, as well as various places in Germany and Israel.
http://www.wrx900.com/