Data Observation Network for Earth (DataONE) is ... a distributed framework and sustainable cyberinfrastructure that meets the needs of science and society for open, persistent, robust, and secure access to well-described and easily discovered Earth observational data. Supported by the U.S. National Science Foundation (Phase 1 Grant #ACI-0830944, Phase 2 Grant #ACI-1430508) as one of the initial DataNets, DataONE will ensure the preservation, access, use and reuse of multi-scale, multi-discipline, and multi-national science data.
Dataverse is an open source web application to share, preserve, cite, explore, and analyze research data. It facilitates making data available to others, and allows you to replicate others' work more easily. Researchers, journals, data authors, publishers, data distributors, and affiliated institutions all receive academic credit and web visibility.
The Dryad Digital Repository is a curated resource that makes the data underlying scientific publications discoverable, freely reusable, and citable. Dryad provides a general-purpose home for a wide diversity of datatypes.
Provides access to a vast archive of social science data. ICPSR's data holdings are for use with statistical software, such as SAS, SPSS, and Stata. A unit within the Institute for Social Research at the University of Michigan, ICPSR has over 640 member colleges and universities around the world. First time users must create an account.
"Nature" asks authors "to submit datasets to an appropriate public data repository. Data should be submitted to discipline-specific, community-recognized repositories where possible, or to generalist repositories if no suitable community resource is available."
SHARE is a higher education initiative whose mission is to maximize research impact by making a comprehensive inventory of research widely discoverable, accessible, and reusable. You can limit your search to "Data Set.".