[Pharo-dev] Looking for suggestions for extended Pharo/Smalltalk intro demo

Hi Folks, I will be teaching a Software Design and Evolution course this Fall in which we use a lot of Smalltalk. For the introduction to Smalltalk lecture I wanted to give an extended demo with some slides in between rather than mainly showing slideware. Does anyone have a good recommendation for an application to build with the students while showing off most of the important features of the language and the environment? Ideally something you have used before in precisely this way. Some things I have used in the past: - Post Office example (small and boring) - Snakes and Ladders (a bit too big) Thanks for suggestions. Oscar