TED Talk: Rajesh Rao: A Rosetta Stone for the Indus Script
In this TED Talk, Rajesh walks through the steps of analyzing the last undeciphered ancient language: Indus. Along the way, you learn several methods for identifying characteristics of languages, plus some innovative computer analysis techniques.
And the bonus is learning about Indus Script and a brief overview of the history of it. If you need to cram study to be a good conversationalist at a party with linguists, this would be a well-spent 17 minutes!