Dermot Bradley
I have been using FOSS software for many years, both as part of my various day jobs and also at home.
I started using Linux-based systems in 1991, and settled on the Debian GNU/Linux distribution which I discovered in 1993 and I was a Debian Project member for several years (1994-1997).
I was the main technical person behind the first Internet Service Provider in Northern Ireland which started operations in 1994. Our ISP used various FOSS packages to run its services such as the Apache WWW server, Exim email server, PHP WWW scripting language, Cistron RADIUS server, Analog WWW statistics utility, and the MRTG network traffic graphing utility, all running on Debian GNU/Linux systems.
These days I extensively use the Ethereal network protocol analyser to aid my day job and I occasionally contribute patches or additional functionality back to Ethereal.
I am also involved with the Linux From Scratch project and run my own custom Linux distribution based on HLFS.