I started writing this in highschool?
I remember my first big personal project in PHP being a website for the MMO game Motor City Online my clan Detroit Lubricators. We stored car setups here for people in our clan to reference. We typically held the weekly records most weeks on our server.
I went on to do the website for powertrain control solutions, ballenger motorsports and iofast in PHP. They were built on phpbb, oscommerce, wordpress and my own bespoke projects.