Google Dataset Search - Dataset Search enables users to find datasets stored across the web through a simple keyword search. The tool surfaces information about datasets hosted in thousands of repositories across the web, making these datasets universally accessible and useful.
Data Citation Index - Indexes data sets from selected repositories around the world, and also enables the user to find data sets which cite a particular work.
Dryad Digital Repository - A curated resource that makes the data underlying scientific publications discoverable, freely reusable, and citable.
Zenodo - All research outputs from across all fields of science are welcome. Zenodo accepts any file format as well as both positive and negative results. Includes publications, datasets, images, software, etc. Sponsored by CERN.