When was the last time a high school senior armed with the power of the internet vowed to take down the Department of Homeland Security (DHS) and actually did it?

Meet Marcus Yallow (a.k.a. w1n5t0n, a.k.a. M1k3y), the narrator of Cory Doctorow's first young adult novel Little Brother. He not only walks the walk, he talks the talk…and becomes in biggest thorn in the DHS' side in all of the Bay Area.

And, although Little Brother was published way back in 2008, it's not an embarrassing relic of an earlier digital age. (There are few things more cringe-inducing than hearing tech talk from an earlier time.)

In fact, this novel's themes of terrorism, privacy, and security are still very relevant today…maybe even more than when it was written.

Here's the deal: terrorists blow up the San Francisco-Oakland Bay Bridge and Marcus & Co. fight back against the DHS's attacks against the Constitution. But don't think that Little Brother is a dusty political treatise—it's super fast-paced. Sure, you learn a lot about encryption technology, but you're also on the edge of your seat wondering what will happen if DHS has their way and shuts San Francisco down.

Fast and furious, this book tackles big questions like: What needs to be kept secret? What should be made public? How important is privacy? What's the role of the Bill of Rights? How essential is transparency for law enforcement? How do you find the best burrito in San Francisco?

It's all here.

The book debuted on the New York Times Best Seller List for children's chapter books and has won multiple awards around the world including the 2009 White Pine Award, the 2009 Prometheus Award, and the 2009 John W. Campbell Memorial Award. It also was a finalist for the Hugo Award for Best Novel.

You'd think with all this success an author would try to sell as many copies as possible—but not Doctorow. In fact, you can read this book right now for free because he gives the book away on his website under a Creative Commons Attribution-Noncommercial-ShareAlike license. So you can download it, listen to it, and remix it however you want, provided you don't sell the results.

We think that makes Cory Doctorow officially awesome.

But the fact that it's an award-winning and insanely popular (free!) book doesn't even scratch the surface of what a phenomenon Little Brother is. It's inspired countless tech innovations. We're talking lots of coding projects. Google even started encrypting its search queries after 2008 because an engineer had read Little Brother and was inspired by the book.

Yup. This book not only changed the lives of the people that read it, it changed Google…which means it's changed the lives of most people on earth. Dang.

The book was challenged for the first time at a high school in Florida in 2014, but it hasn't been banned anywhere (yet). Publisher Tor Books and Doctorow responded by giving the students two hundred free copies.

Ready to see what all the fuss is about and learn some hacking tips along the way? Time to strap in.

Let's start with a short quiz:

• Who is watching you right now?
• Do you know?
• Do you care?
• Could you prove that you're not a terrorist if asked by a member of law enforcement?
• Just what makes someone a terrorist anyway?
• Can you really spot a terrorist just by looking at them?
• Do increased security measures help stop terrorism?

Heavy stuff? Yes.

But as terrorism continues to be in the news headlines, it remains hard to say what exactly makes someone a terrorist. Is the old cliché true that "one man's terrorist is another's freedom fighter"? Isn't that oversimplifying matters? How can a government balance the needs of security and civil liberties?

We know; we know. We're asking a lot of hard questions. But not only are these questions crazily important if you're living in the 21st Century (all those ghosts reading this; you're off the hook), but they represent just a fraction of the questions that Little Brother poses.

In Little Brother we're inside the head of someone who wants to keep his country safe, but that some government agents see as a huge threat to that same country. In fact, Marcus Yallow makes many of the same arguments that real-life controversial figure Edward Snowden made after releasing details about what information U.S. intelligence programs were collecting in 2013. (Fun fact: in the documentary Citizenfour, Edward Snowden had the sequel to Little Brother on his nightstand.)

As the debate about what the government should be allowed to monitor and what should be kept private continues, we seem to be no closer to clearly defining what makes someone a terrorist and how we can keep citizens safe.

Think we're over-exaggerating the case? Check out some of the things America's current surveillance program can see. Gait detection cameras might not be the norm (yet), but there's still plenty that makes us feel a little too close to 1984.

So look around, know who's watching you, and get your mitts on a (free!) copy of Little Brother.