UNdata brings together official statistics produced by countries and compiled by United Nations data system, as well as estimates and projections. The domains covered are agriculture, crime, education, energy, industry, labour, national accounts, population and tourism. You can also find indicators such as Millennium Development Goals.
For nice visualizations using UNdata as a source see Progress: A Graphical Report on the State of the World and Gapminder.

EOLSS comprises nearly 600 book volumes of thematically organised, peer- reviewed state-of-the-art content. EOLSS is one of the largest community oriented encyclopedia creation projects of the world, with contributions coming from several thousand renowned scholars from more than 100 countries.

The main topic of EOLSS is science of sustainable development. The 21 component encyclopedias cover topics such as «Development and economic sciences», «Desalination and water resources», «Land use, land cover and soil sciences» and «Water sciences, engineering and technology resources». Natural and social sciences, humanities, engineering and technology, and management policies for sustainable use of life support systems are emphasized, together with issues of global change and their ecological, economic, social, ethical, cultural, and political dimensions.