World Bank, UNIDO, IMF, OECD, ECB, EUROSTAT
AllThatStats (ATS) provides direct access to approx. 65,000 databases with around 1,000 million time series from official sources. Regularly updated it's an unique repository of the world's most important statistical data collections.
AllThatStats revolutionises your work with official statistical sources.
Example: How to automate your workflow with ATS
Example: Communicate statistics with your mobile devices directly via Twitter, Facebook or WhatsApp
DSI research: Geospatial information - combining statistics and geographical data (free access)