If anyone is interested in Carmack's backstory I recommend picking up a copy of "Masters of Doom: How Two Guys Created an Empire and Transformed Pop Culture." It was published in 2004 so don't expect any of the newer stuff he has done but it is quite the read.
Whenever I need inspiration, I read that book. John Romero was an interesting character, but John Carmack is the whole point of that book to me. His work ethic and drive to continually improve his skills are so inspiring and rewarding.
In a similar sort of vein, "Show Stopper!: The Breakneck Race to Create Windows NT and the Next Generation at Microsoft" is a great recaps of the initial Windows NT days with David Cutler and his 200+ ex-Digital OS engineers.
It was published in 1994 (so covers up to Windows NT 3.5 and touches on Chicago/Win95) and features a lot of info gleaned from 1:1s the author had with Gates, Cutler and a host of other executives.
(The design decisions made back then between 89-93 for NT are what enabled things like 'Bash on Ubuntu on Windows' to take place today.)
