Her new book, Dragnet Nation, talks about the difficulties involved in avoiding today's relentless surveillance—not just from the government, but also hackers and corporate collectors of information.

"Every day it's a hassle for me to protect my and my family's privacy. Some days you're just a vegetarian, some days you you're all vegan," she said.

Still, there are simple privacy tools available. They're not NSA-proof, but go a long ways towards erasing the digital breadcrumbs we all leave behind us.

Ghostery

This is an easy browser add-on. "All of the sudden, you can see all the different companies on a site that are trying to track you, and you can choose whether you want them to," said Angwin.

Be aware that blocking all cookies, tags and web bugs can make some sites harder to use.

Disconnect

This is another program that filters out companies that are watching what you do, and also offers encrypted communication when you send information to other sites so eavesdroppers can't see your data.

DuckDuckGo

This is an anonymous browser that doesn't store or sell data about you. So if you search on herpes treatments, you won't suddenly find a slew of ads for herpes suppression the next time you go online.

Two-factor Authentication

Many online services already have a great way for users to protect themselves against hackers. All the user has to do is turn it on, said Simson Garfinkel, a professor of digital forensics and computer security at the Naval Postgraduate School in Monterey, Calif.

It's called two-factor authentication,.

With Google's gmail, for example, Google recognizes when someone is trying to log in to an email account on a different computer from the one they usually use. That's a red flag that a hacker might be trying to get into the account.

Google sends a code to the account-holder's cell phone that they then have to type in before they can access their email on the new computer.

Encrypt your hard drive

It's easy to get at everything on a computer—all someone has to do is steal it and then riffle through your digital life at their leisure. But encrypting the computer's hard drive stops that cold.

Newer versions of Windows and Mac come with the ability to do this built in. For Window's users, it's called BitLocker and for Apple users it's FileVault. Both offer easy-to-follow tutorials on how to enable the function.

Private web surfing

If you won't want anyone to know where you go or what you do online, several options are available. One, which Snowden referenced in his talk, is called Tor. It's free software and a network that allows users to visit websites without anyone being able to know which ones. The sites also can't pinpoint a user's physical location. It can also slow down browsing.

Other options include paying for a commercial Virtual Private Network. These offer secure connections that guarantee the data you're sending is encrypted and can't be seen by hackers or others who might want to spy on you. A quick search online should bring up several lists of good ones.

Email

Email is still "surprisingly hard" to do securely, said Bruce Schneier, a security expert at the Berkman Center for Internet and Society at Harvard Law School.

The available programs are still "too hard and not intuitive," he said. One stumbling block is that users must first exchange encryption keys. "It's like language. If you don't speak French, I can't speak to you in French no matter how hard I try," he explains.

So far one of the more user-friendly email encryption programs is PGP. There are multiple online tutorials to walk you through the process of using it.