Not as much as I'd like, always seems like there's something else more important to do, or when I do take downtime something more convenient (video games, etc).<p>Mostly SciFi, the harder the better. Entertainment value aside it's where I draw inspiration from, I'm basically an engineer because I watched/read a lot of sci-fi as a kid and thought it would be awesome if we could build all the stuff shown. In 5th grade when asked to "come up with an invention" I drew my best 5th grader blueprints of a probe to explore under the ice of Europa :P<p>Turns out there are a few pesky laws of physics in the way of some of the cooler stuff, but just because we can't build it directly doesn't mean we can't move the ball closer, and new physics is always a possibility. In the meantime there's plenty of awesome things we can do with the tech we have.<p>When I do read non-fiction it's almost always history, particularly military history. Aside from simply finding it more engaging I find the strategic aspects of war to be highly applicable to daily life and decision-making. Much like engineering, dishonesty about one's capabilities is not rewarded for long. If you can't code effectively your program won't run, if you can't fight effectively you lose the war, and more things are decided by superior logistics than superior warriors, among many other lessons that can be drawn.<p>I probably differ from a lot of the HN crowd in that I don't spend much time reading about abstract theoretical science. For instance, for all the talk about "mental models" I've yet to see any way of productively integrating such things into my life, or found one that would lead me to make superior decisions when applied to real-world circumstances. Clearly others have and that's fine, I just don't personally find it a useful/enjoyable way to spend my time. Likewise I once read about "Optimal Stopping Theory" as applied to relationships, the idea being using mathematics/statistics to maximize one's odds of a successful marriage. The methodology was actually impressively in-depth, I forget the precise numbers, but it was something like you should skip the first few people you seriously date, then pick number 4-7 or something, and that gave you like a 40-something percent chance of success, which was the maximum. Well my wife is the first person I ever dated more than once and I have no regrets there, so if I strictly followed that formula it would have been a huge mistake.<p>Lots of squeeze, not much juice in the theoretical stuff for me.