Of the 7,000 or so languages spoken in the world, half could be gone by 2100. Two linguists are using digital recording technology and the Internet to try to preserve these languages in what they call "talking dictionaries." The dictionaries so far contain more than 32,000 word entries in eight endangered languages, with over 24,000 audio recordings of native speakers pronouncing words and sentences.
The work of K. David Harrison (Swarthmore College) and Gregory Anderson (Living Tongues Institute for Endangered Languages) includes preservation of languages, like Koro, that have never been recorded before. Koro is a language spoken by only a few hundred people in northeastern India.
Here's a link to an interview with David Harrison on National Public Radio's "Science Friday," and here's an article on Science Codex. The picture (taken from the Wall Street Journal website) shows Harrison with John Agid (left), who is one of only 600 speakers of Matukar Panau, a language of Papua New Guinea.