Making Drupal fun?

I’m giving a 6 hour Drupal workshop in a University next week (over 3 days). I need a example Drupal application that can be built in an hour. (In the workshop we’ll do it over 4 hours). I’d like to demonstrate that Drupal is fun and inspire them to learn more. The students are mainly from Computer Science.

My plan was to build a Vacation Approval System. So an employee can create a form applying for leave. An email is sent to their manager with a link. The manager selects to “Approve” or “Decline” the leave application. An email is sent to the employee with the manager's answer. It uses the module Workflow and Rules to send email and Entity Reference to link Employees with a Manager. I did a test run of this today with a small group of students. I hate to say this but it was boring. There was just so much configuration - it was painful. It demonstrated the power of Drupal in building applications but it didn’t feel like fun.

Has anyone done a fun Drupal demo? Or maybe - how I can make the demo of the Vacation Approval System more interesting. Ideas?