another one to try
I once tried to learn Visual C++, and had a coworker that was religiously devoted to using only Netscape as his browser, he was convinced that IExplorer was an evil plot by Bill Gates (he was a visionary)... So I made a little popup window that came up when he clicked the Netscape button, It explained that windows would no longer be compatible with netscape, so the computer could not start up Netscape.
The poor guy nearly had an anuerism...