Gödel, Escher, Bach: an Eternal Golden Braid — Douglas Hofstadter
Logic for Mathematicians – A. G. Hamilton
The Black Prism — Brent Weeks
I like to be reading 2-3 books at a time, but one gets my full attention, and the others switch up the pace for me otherwise. I like "serious" books (GEB, Logic) interspersed with "easier" books; a classic, sci-fi/fantasy, etc.Read when you'd instead be surfing HN or Reddit and when you're done coding/working on homework. Reading takes the place of procrastination very nicely—the same relaxation, but less guilt and more benefit.