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Psych books I've read
"Predictably Irrational" and "The Upside of Irrationality" by Dan Ariely. Basically what it sounds like; how and why and when people behave irrationally. Both very readable.
"The Happiness Hypothesis" by Jon Haidt. Again, pretty much what it sounds like; what makes people happy, and what doesn't, along with some other miscellaneous psych goodies.
"The Dream Drugstore" by Allan Hobson. This explains what's going on in your brain when you're sleeping, with an emphasis on dreaming. It's a bit technical, perhaps more on the neuroscience side than the psychology side, but it discusses (and largely refutes) Freudian theory.
Any of Oliver Sachs's books are interesting, though light-weight, looks at clinical psychology.
"The Lucifer Effect" by Philip Zimbardo discusses how ordinary people can do awful things. He's the guy who ran the infamous Stanford Prison Trial, and the first half of the book is dedicated to that.
"Gut Feelings" by Gerd Gigerenzer describes how many unconscious processes produce "gut feelings" that actually turn out to be more successful than cold, sober reasoning. It's fascinating.
"Calculated Risks", also by Gerd Gigerenzer discusses how the human brain is not equipped to process statistics on an intuitive level, and how people who should know better (eg doctors) routinely fub their statistics.
"The Blank Slate" by Steven Pinker is a classic nature vs nurture discussion that critiques that argues largely in favor of the power of genetic influence on behavior, critiquing modernism, post-modernism, and feminist theories of psychology, among others.
"The Stuff of Thought", also by Steven Pinker, is a linguistic approach to how various mental faculties do what they do. It can be dry, but it's certainly enlightening.
I'm probably forgetting a few, but that's a start.