TravLang Translating Dictionaries
18 major languages plus others.

Ethnollogue.com: Languages of the World
A comprehensive listing of information about the currently known languages of the world. Included are bibliographic citations for thousands of published works with additional information about the languages of the world and maps which include most of the countries of the world.

I Love Languages
A comprehensive catalog of language-related Internet resources. The more than 2000 links have been hand-reviewed and contains online language lessons, translating dictionaries, native literature, translation services, software, language schools and more.

Yahoo! Languages
Links to chats & forums, endangered languages, language families, specific languages, web directories and more.

Language & Linguistics Extensive links from the Internet Public Library