After the success of DrupalCon London back in 2011, the local user group decided to run a regular camp in the capital.
As with the official conference before it, the event was well was very received and I personally found huge benefit from my attendance.
I hadn't heard of David Axmark before the keynote but I had heard of MySQL, probably the world's most popular open source database. Axmark told the story of how the startup was born and how it became the platform of choice for the web development and hosting industry. When the company was eventually bought out by Oracle they all became millionaires but David Axmark still wanted to make databases.