This post is old, but looking on Google for something similar to a "command-line social-networking" app I came across this idea. And with everyone using GitHub for everything now, maybe it could be possible... with a little work.
Seems a decent educational tool too.. run in a virtual box and let your students go all out overflowing buffers and seeing the concepts in action. It comes with easy-to-follow guides.
OK for learning about what has been solved; kind of hacking-101. BUt the exploits involved have all been fixed in the products in that distro. What to use for the advanced class?