One of the course videos is about "Why isn't there only one language?". Another is: "What defines a language". Here's the course page: https://www.coursera.org/course/humanlanguage
And a second link: Ethnologue is an online database of the languages of the world: "Ethnologue contains information on 7,102 known living languages. Begin by clicking World Languages in the page header...."
While browsing Ethnologue, I remembered the language installation I once put together. The photo above is a screenshot of it, here's the moving version: "forms of being",
And here's the original publication in qarrtsiluni's "Translation" issue: forms of being
On another note, I think I will go and revisit links from the past more often. So much out there, or rather: so much back there.