NPR just ran a little piece on the Harrison et al. project on endangered languages. Nice thing is, they included a lot of little sound files, words or phrases in endangered languages. Audio should be up here in a few hours, here. But the best thing is to check out the project's map directly, here.
Major update: See here. Apparently reports on the project (maybe the project itself) didn't exactly get some major facts right, and in some serious ways.