This multi-disciplinary database has records for nearly 18,000 periodicals - journals, magazines, and newspapers - of which nearly 16,000 are peer reviewed. It provides full text for more than 5,000 journals, and you can use Journal Finder to locate articles that do not have a PDF readily available.

Searchable field guide to the bird species of North America, with keys to identification. Maintained by the Cornell University Lab of Ornithology. Includes sound and video clips.

Sponsored by the American Society for Cell Biology (ASCB), this open-access crowdsourced collection of images and multimedia files is browsable by cell process, cell component, cell type, and organism. The database also provides basic- and advanced-search options, and a free “Cell Library” app for iPhone and iPad users.

GreenFILE offers well-researched information covering all aspects of human impact to the environment. Its collection of scholarly, government and general-interest titles includes content on global warming, green building, pollution, sustainable agriculture, renewable energy, recycling, and more. The database provides indexing and abstracts for more than 384,000 records, as well as Open Access full text for more than 4,700 records.