US Intelligence Data
The CIA World Factbook is an up-to-minute global database of history, people, government, economy, geography and on many more categories.It lists 267 world entities, in most cases these are countries. In addition it also includes various thematic databases, eg. political map, flag database, etc. The database is slightly US focused, see eg. the map of Hungary layered on a USA map.
Britannica Online is the 21st centrury edition of the Encyclopædia Britannica founded in 1768. The online version preserves the authority of the famous reference work and adds interactive cross-references and multimedia. Contrary to Wikipedia, the authors of Britannica are not volunteers but selected experts.
Geoba.se is provides a gazetteer with key geographic information about any location. This is a combined database of multiple public sources. Each gazetteer entry shows information like population and rankings, nearby Wikipedia articles, nearby webcams and many more location specific details. It does not contain any original data, but the way of presentation is really unique.