As mobile technology and social networking have become commonplace, so have concerns about privacy. In fact, nearly every day the media covers stories about identity theft, social networking "pranks" gone wrong, companies with shady privacy policies and repressive governments that censor and monitor online activities.
In this environment, protecting your privacy is an absolute necessity.
Fortunately, the open source community has stepped up with a variety of tools designed to protect your personal data. Whether you're an average individual who wants to avoid divulging personal information or you're a journalist, activist or someone else who needs complete online anonymity, these tools can help you keep your private information private.
If you'd like more details about how to protect your privacy online, you might want to check out We Are Hidden or The Tor Project, two groups associated with the open source movement that have done a lot of work in the privacy arena. You can also find more information about the topic from The Electronic Frontier Foundation, Privacy.org and The Privacy Rights Clearinghouse. Armed with tips from those organizations and the open source apps listed below, you should have plenty of tools to help protect your privacy.
1. Tor Browser
The Tor project protects anonymity online by sending communications through a distributed network of relays so that it cannot be traced. This browser is used by many journalists, activists, military organizations and others who need to remain completely anonymous online. Operating System: Windows, Linux, OS X.
This research project uses similar technology as Tor to obfuscate the Web addresses of users. It encrypts online communications and routes data transfer through a predetermined set of "Mixes," or intermediaries that promise not to save log data or share it with others. Operating System: OS Independent.
Mixmaster claims to be the most popular implementation of the type II remailer protocol. With it, you can send email anonymously or under a pseudonym. Operating System: Windows, Linux.
The reference implementation of the Type III Anonymous Remailer protocol, Mixminion also protects the identities of email senders by routing it through a network of servers and using encryption. According to its designers it "protects against known anonymity-breaking attacks as well as or better than other systems with similar design parameters." Operating System: Windows, Unix, OS X.
This app describes itself as a way to send "fake" email. You can use it send email that looks like it comes from any email address you like. Operating System: OS Independent.
Based on SpamAssassin and ClamAV, MailScanner runs on mail servers and protects against malware and spam. It's been downloaded more than 1.3 million times and counts portions of the U.S. government and military among its users. Operating System: Linux, Unix.
Calling itself "The powerful #1 open-source spam filter," Apache SpamAssassin uses an entire arsenal of network and local techniques to identify and block spam. It can be used at the mail server and/or at the local email client. Operating System: Windows, Linux, OS X.
This tool uses statistical filters (sometimes called Bayesian filters) to classify mail as spam (undesirable messages) or ham (desirable messages). Unlike some other types of anti-spam software, you must first train the software by telling it which types of messages you read and which you consider spam. Operating System: Windows, Linux, OS X.
Nixory seeks out and destroys malicious tracking cookies. It works with Firefox, IE and Chrome, and it can delete cookies in real-time without noticeably slowing performance while you are browsing. Operating System: Windows, Linux, OS X.
10. Hijack This
Downloaded more than 1.2 million times, Trend Micro's Hijack This provides you a report of your registry and file settings so that you can more easily spot and remove spyware and malware. Note that in order to use this tool effectively, you'll need to be a fairly knowledgeable user. Operating System: Windows.
Dooble describes itself as "a mischievous and platform-independent browser" and also as "fair trade and organic software made with lots of love." It includes several privacy protection features, including encrypted cache and an easy-to-use cookie manager. Operating System: Windows, Linux, OS X.
12. SRWare Iron
Based on the same Chromium code that underlies the Chrome browser, SRWare Iron aims to offer the performance benefits of Chrome with enhanced security and privacy protection. Unlike Chrome, it doesn't send any tracking, address bar or download data to Google. Operating System: Windows, Linux, OS X.
13. HTTPS Everywhere
A collaboration the Tor Project and the Electronic Frontier Foundation, this Firefox and Chrome plug-in accesses sites via https instead of http whenever possible. As a result, it encrypts most of your communications with many websites. Operating System: OS Independent.
Created by the World Wide Web Consortium (W3C), this Firefox shows you at a glance whether the site you're visiting does a good job of protecting your privacy or not. And the first time you visit a site, it gives you the ability to set up preferences for what kinds of information you will share with that site. Operating System: OS Independent.
This extremely popular Firefox add-on has been downloaded more than 59 million times. It rates sites based on their trustworthiness, privacy practices, reliability and child-friendliness, and it uses a color-coded signal (red-yellow-green) to indicate if a website is safe to trust or not. Operating System: Windows, Linux, OS X.
Prevent websites from snooping into your browsing history. This Firefox add-on works with your cookie settings to segment your cache and protect your privacy. Operating System: Windows, Linux, OS X.
This Firefox add-on protects against Flash cookies (a.k.a. "Super Cookies") that websites can use to track your activities even when you have cookies disabled. Note that if you play any online Flash-based games, you will need to have this add-on disabled in order to save your scores and game progress. Operating System: Windows, Linux, OS X.
18. AdBlock Plus
With more than 15 million uses, AdBlock Plus is one of the most popular add-ons available. It allows you to block all advertisements (and their related tracking cookies) or just "unacceptable" advertisements that don't meet the criteria specified by the app developers. Operating System: Windows, Linux, OS X.
PasswordMaker acts as a portable, online password safe. It creates strong, secure passwords for each of your online services, but you need only remember a single master password to access them. Operating System: Windows, Linux, OS X.
Based on KeePass, KeeFox is a password safe for all of your online passwords. Plus, it can also store non-Web passwords, and it works with sites that have multiple login pages or steps. Operating System: Windows, Linux, OS X.