Interesting programming languages for presentation
RiderOfGiraffes: Thinking again, I would give a complete implementation of Lisp.  You can define EVAL and APPLY in about 4 slides. That lets you have a 1 minute intro, 3 mins per slide, 1 minute conclusion, and 1 minute for questions.If they've seen this before in class then you obviously can't do it, but it's historically significant, and interesting from an academic POV.