Over the years, I've met lots of libertarians who have told me how big a deal for them was J. Neil Schulman's 1979 novel Alongside Night. It's a dystopian tale that explores the philosophy of Agorism (read more about that here).
Schulman is more into making movies these days than penning novels and he directed a version of the film that was released in 2014 and is now streaming on Amazon Prime and elsewhere. It stars Kevin Sorbo, best known as TV's Hercules. A trailer is above.