The Dune series by Frank Herbert. Unlike anything else I've read, and one of the most compelling and detailed fictional universes in literature.
The Discworld series by Terry Pratchett. Don't confuse it for fantasy - it's brilliant satire. Littered with geeky references and clever wordplay, I actually enjoy it a bit more than the Hitchhiker's Guide books. If you like Douglas Adams, Terry Pratchett is a pretty safe bet.
Anything by Stanislaw Lem - clever and funny science fiction. A good match for my weird sense of humour.
All of the above can slightly change the way you see the world.
For non-fiction, another vote for the Mythical Man Month.
I was going to mention Dune. That series taught me an important lesson: the techniques of mind, and the mind-body interface, are a technology - and we are still in the dark ages. We do not know how to learn, how to teach, how to make best use of our brains to analyze or synthesize. We are generally blind to our own minds and bodies and running nine tenths of the time on autopilot. When individuals get these skills, it's by aptitude or discovery. We haven't systematized them, we haven't made a science of them, we certainly don't teach them in school. There's a lot of room for improvement.
The Dune series by Frank Herbert. Unlike anything else I've read, and one of the most compelling and detailed fictional universes in literature.
The Discworld series by Terry Pratchett. Don't confuse it for fantasy - it's brilliant satire. Littered with geeky references and clever wordplay, I actually enjoy it a bit more than the Hitchhiker's Guide books. If you like Douglas Adams, Terry Pratchett is a pretty safe bet.
Anything by Stanislaw Lem - clever and funny science fiction. A good match for my weird sense of humour.
All of the above can slightly change the way you see the world.
For non-fiction, another vote for the Mythical Man Month.