I really like nonfiction, so I'll recommend a few.
Wonderful Life (Stephen Jay Gould) was what really helped me understand biology. Really interesting read if you want to hear about evolution or paleontology. If you prefer land animals to Cambrian bugs, Rise and Fall of dinosaurs (Steve Brusatte) is also a great read, though it didn't blow my mind as much as Gould did.
House and Soul of a new Machine (both by Tracy Kidder) are op opposite ends of the technical spectrum but together form a rich portrait of people at work.
Exploding The Phone (Phil Lapsely) is the book you want if you're at all interested in retro technology. I suspect many people who care enough to use a ln offbeat social network like this one will enjoy it.
Annals of the former world (John McPhee) is a hefty tome that tells the natural history of United States geology, the history of geology (especially how plate tectonics were discovered) and how geology has interacted with the people living on it.
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