Wikipedia, the free-content encyclopedia that anyone can edit.

Wiktionary, a collaborative project to produce a free multilingual dictionary.

Wikibooks, a collection of open-content textbooks that anyone can edit.

Wikiquote, a free online compendium of quotations in every language.

Wikisource, a repository of primary source texts in any language that anyone can edit.

Wikinews, the free news source (BETA) that you can write.

Wikispecies, an open, free directory of species.

Wikimedia Commons, a project that provides a central repository for free images, music, sound & video clips and, possibly, texts and spoken texts, used in pages of any Wikimedia project.

Meta Wiki, the support website for Wikimedia Foundation's projects.

• Google Images
• Froogle (Google Shopping)
• Google Answers
• Scholarly Google