A site with geopolitical data, statistics on the human population, Earth and more. The main kind of data you can find here is population statistics of regions, countries, provinces and cities. Next to that there are some statistics on economic factors like wealth, infrastructure; statistics on natural phenomena; etc.
The GGDC 10-Sector database provides a long-run internationally comparable dataset on sectoral productivity performance in Asia, Europe, Latin America and the US. Variables covered in the data set are value added, output deflators, and persons employed for 10 broad sectors from 1950 onwards.
A massive central data source and a handy way to graphically compare nations. NationMaster is a vast compilation of data from such sources as the CIA World Factbook, UN, and OECD. Using the form above, you can generate maps and graphs on all kinds of statistics with ease.