American Economic Association Data and Code Repository
As part of its data availability policy, the American Economic Association requires authors who wish to publish in AEA journals to provide replication data and code for those publications in this repository, which is one of the ICPSR's collection of open repositories.
Harvard Dataverse Network (DVN)
Harvard's Dataverse Network is an eclectic collection of datasets and data collections, including replication datasets for articles on topics such as political competitiveness in post-war Latin America or the effect of IMF programs on government spending, ongoing research projects on topics such as manifestos of regional political parties and ideology scores of state legislators and perceptions of electoral integrity, organizations such as development NGOs, groups such as networks of economists at different universities, and replication archives for academic journals.
National Bureau of Economic Research (NBER)
In addition to its work on business cycles, the NBER has an eclectic data archive that covers topics such as cross-national technology adoption, manufacturing productivity, financial openness and exchange rate regimes, and economic policy uncertainty. Its data archive also covers topics such as labor markets, health economics, and population demographics.
World Bank Data Catalog
As part of its Open Data Initative, the World Bank has opened up access to dozens of its data collections and compiled into a single data catalog. The holdings here range from larger databases covering multiple topics to more narrowly-focused collections associated with particular research projects. You can also search for World Bank data by country or by looking for specific indicators.
Selected Data Resources for Economists
A compilation of commonly-used data resources covering economic indicators as well as both U.S. and international data sources for health, demographics, and other topics.