I'd be inclined to a pretty informal walk through of the highlights of the code that catalyzed the "seminar" with an intent of generating a series of "That's cool", and "Neat!". There's not enough time to really introduce the language enough that anyone is going to go off afterwards and write an opus using it, but you can flash enough neat stuff before them to stimulate some interest in following up. Treat it more as a question and answer session with a small number of natty code samples.

And of course when they ask where to find out more, you know where to point them. ;)