PHP Code Example Idea

So I need to create PHP code example for a job lead.  I haven't used PHP for non-trival work in quite a number of years, and owing to a hard drive crash I lost just about every subversion repository of PHP code I had written in the past.  There wasn't anything terribly valuable to me in the lost code (hence why it wasn't backed up), but now I don't have anything I could quickly zip up and send.

So I need an idea of something fairly quick and simple to write, but shows off reasonable competency of the language and programming in general.  This is a entry-level software engineering job, so it can probably be pretty simple, but as long as it doesn't take me more than evening I don't care.

A simple CMS.

rewrite /prog/scrape in PHP

Obviously, you should write a LISP interpreter.
More realistically, for a ``software engineering'' position, something with AJAX and both MVC and Singleton design patterns is appropriate- an "in browser" multiplayer connect four game perhaps comes to mind. A live PL/0 parser/compiler/interpreter. A program that zips itself up and sends it (i.e.: writes the pdf out to file from strings, writes some samples out to file, (including file_get_contents(__FILE))) and then zips and mails it all. For extra credit write all the library code yourself.