AidData is a portal for an extensive database of development assistance. Users can query the data by combinations of aid recipient, aid donor (individual countries and multilateral organizations), year, and aid purpose. The AidData project has a separate site devoted to Chinese development finance.
British Petroleum Statistical Review of World Energy
The Statistical Review of World Energy is a very good source for international time-series data on energy production and consumption, with a collection of downloadable data here.
International Monetary Fund (IMF) Macroeconomic and Financial Data
The IMF's data library covers topics such as investment flows, monetary aggregates, economic output, commodity prices, exchange rates, public finances, financial institutions and markets, and both public and private debt. The available databases include the Balance of Payments Statistics, the Direction of Trade Statistics, the Government Finance Statistics, and the International Financial Statistics.
International Monetary Fund (IMF) Primary Commodity Prices
The IMF publishes monthly reviews on commodity prices and price forecasts. As part of this program, the Fund makes available a collection of monthly prices and price indices for various types of commodities.
OECD Query Wizard for International Development Statistics (QWIDS)
QWIDS is a (relatively) accessible interface for very detailed data on foreign aid and development assistance that allows you to break down aid flows by combinations of recipient, donor, and purpose of aid.
United Nations Commodity Statistics Trade Database (Comtrade)
The UN's Comtrade database is a good source for commodity-specific bilateral trade data. Users can create their own extracts of data for both value and quantity of trade using different industrial classification codes and download those extracts for later use. Comtrade now also includes data on trade in services. This resource is also available via Databases at Emory.
World Bank Global Economic Monitor Commodities Data
"The World Bank collection of monthly commodities prices and indices from 1960 to present, updated on the third working day of each month, as presented in the Commodity Price Data (a.k.a. Pink Sheet), published continuously for more than half a century."