Web Directories:
Invisible Web Directory Access the "invisible web" through LII (look for "databases" in your results)

CompletePlanet A comprehensive listing of dynamic searchable databases in the "hidden web". Helps you to find databases with highly relevant documents that cannot be crawled or indexed by surface web search engines.

Subject Directories:
Academic Info an independent online subject directory of over 25,000 hand-picked educational resources for high school and college students.

Digital Librarian - a librarian's choice of the best of the Web

Stanford Encyclopedia of Philosophy A scholarly and dynamic resource maintained by experts in the field of philosophy.

Encyclopedia of Life The Encyclopedia of Life (EOL) is an ambitious to organize and make available via the Internet virtually all information about life present on Earth. At its heart lies a series of Web sites—one for each of the approximately 1.8 million known species—that provide the entry points to this vast array of knowledge. Very cool!

Scirus Science Information and Resources the most comprehensive scientific research tool on the web. With over 450 million scientific items indexed at last count, it allows researchers to search for not only journal content but also scientists' homepages, courseware, pre-print server material, patents and institutional repository and website information.

Monterey Bay Aquarium The aquarium project was initiated in 1977 by a group of four marine biologists at Stanford's Hopkins Marine Station in Pacific Grove, and it opened October 20, 1984. Great resource!

OAIster is a union catalog of digital resources which provides access to these digital resources by "harvesting" their descriptive records.

Directories
Directory Times
Ezilon Web Directory
Best of the Web! Lists content-rich, well-designed websites categorized both by topic and by region. This is a paid for service.
DirJournal
Skaffe.com
WoW
Sporge
WoW Yellow Pages
ODP or Open Directory Project (aka DMoz or ODP) - The largest directory of the web. Its open content is mirrored at many sites, including the Google Directory.

General

Specialist Directories

  • Biographicon - a directory of biographical entries
  • Business.com - Business directory which charges a fee for review and operates as a Pay per click search engine.
  • VFunk - Online directory that specializes in listing and categorizing global dance music and urban lifestyle listings.