It lead me towards building websites and writing about games, and out of the Quake community I met people who ran Unreal websites - they gave me a copy of their CMS, and I ended up learning PHP/MySQL from it and building and designing bigger and better websites.
I dropped out of my Mechatronics/CS degree to pursue programming for a living - which lead to my first exposure to the then-revolting idea that programming and design were different disciplines. I spent years bouncing back and forth between the two, never quite fitting in, but learning a ridiculous amount along the way.
Now I'm at Google, technically employed as a software engineer but leading the design of a large product. I probably would have ended up somewhere in the software industry anyway, but I believe that I'm in this exact position, the best job I could possibly imagine, because of a chain of coincidences that were kicked off by Quake and its modding tools.