Steffan Heuer and Pernille Tranberg are authors of the book "Fake It: A Guide to Digital Self-Defense." They cover technology and privacy issues in San Francisco and Copenhagen. In this series, Digital Self-Defense, Heuer and Tranberg report with updates from the digital identity wars and teach us how to defend our privacy in the great data grab going on all around us. Follow them at @FakeIt_Book.

Why care about privacy? You have nothing to hide, right? And you're not remotely interesting, so why should anybody want to keep an eye on you? Because information about the real you online is valuable to more than just hackers and scammers—it's becoming the very fuel driving the economy. Concrete information on each and every one of us is worth literally billions. There will be blood in the race to tap it.

Personally, we're mad as hell about being tracked on every site; having our pictures and those of our children hijacked on social networks; having our personal data and credit card numbers exposed. We know that our supermarket, our bosses, insurance companies, banks and many more keep looking over our shoulders online.

Here's just a few ways that loose bits of real info about you can sink your career or even your private life: tweet something stupid about your country, and risk being turned away at the airport. Post something that seems offensive to your colleagues, and your boss fires you. Share your skydiving hobby or your fast driving habit, and your insurance company raises your premium or worse, denies life insurance coverage.

Free is the default for online services, but we are actually paying a very high price—we pay with our data. Companies collect pieces of our identities without our informed consent or knowledge and build huge identity banks that are worth billions.

Take control of your data by hiding the real you

It will only get worse unless we take back the control of our data. We should all be able to decide and control what others know about us, in which context. At the moment, there are not many options for protecting this information, since each site ultimately controls what information they require of each user. In order to use a site, you must click that “I agree” button and accept their terms of services.

The most important tool we have at our disposal to fight back is actually very simple: the use of multiple, fake identities and profiles. By fake profile, we mean just that: a fake name, a random birthday, a fake username different age or address—whatever information is required of you, just invent it. It sounds too simple to work, but it’s actually an effective first step in keeping the “real you” out of the reach of marketers and big corporate data information compilers. They may have access to some information—your photos, your use of certain websites, perhaps some comments and tracking code on your machine—but without the ability to easily trace back to a “real” person, this data becomes meaningless.

Some techies like Facebook founder Mark Zuckerberg argue that it's dishonest or suspicious to remain anonymous online. We disagree. Besides the obvious fact that we are only valuable to companies like Facebook if we use a real name so we can be subjected to data-mining and targeted ads, there are plenty of other legitimate reasons to be anonymous or use a pseudonym. How about, for example, the silent safety needed for whistle blowing, and for being able to speak the truth while protecting yourself and your sources?

And what about all those who just want to be left alone, who want to participate socially online, but don't want to become a machine-readable human? If you don’t want to give up using Facebook, Pinterest, Twitter or Instagram, use a fake, invented username and account. Anonymity does and can have powerful benefits. It should not be reserved for a few professions or seen as only a tool for crooks.

Set up as many pseudonyms as you need to. It's a manual process today, but plenty of startups and companies—Abine’s MaskMe, or Leemail.com, as well as patents taken out by Apple and Google—are working on software that will soon make it as easy to switch between multiple identities as it is to switch between venting to a friend and conversing with a work colleague.

This is just the beginning of a movement to defend our identities and fend off the uncontrolled and under-legislated data grab going on all around us.

Stay tuned as we bring you updates from the frontline of the coming identity wars.

Photographs by Thomas Kern, Anders Debel Hansen

Illustrations by Jeff Pastorek