These days, the ability to browse the web anonymously is built into most web browsers. Firefox has a special Private Browsing mode where no trace of your history -- including searches, downloads, web forms and cookies -- is kept, although any downloaded files and bookmarks will remain as evidence of your secret browsing session.
It’s certainly more robust than a general browsing session, but it’s not as secure as it might be. That explains the reasoning behind Private Browsing by PortableApps.com 3.0, a free add-on for Firefox Portable Edition for Windows.
Firefox Portable Edition is -- as its name implies -- a standalone version of Firefox for Windows PCs that can be run directly without installation, making it perfect for portable use on a USB drive. It too has the Private Browsing mode offered in the regular Firefox build, but install the Private Browsing add-on and you can go further.
The add-on is launched separately from Firefox Portable, but then loads the parent application with its own customized profile in place. This sets things up in the same way a regular Private Browsing window would, with privacy risks such as cookies, download history and so on switched off, but it goes further.
Private Browsing comes with the Flashblock add-in to block Flash-based cookies, which aren’t covered by Firefox, and AdBlock Plus (and a subscription to EasyPrivacy) to block tracking scripts and sites. It maintains its own separate list of bookmarks, allowing you to bookmark sites without them showing up in your regular list. All other Firefox add-ons are disabled too, so they can’t record any compromising information during your private browsing session.
It’s not perfect -- the authors themselves point out that it’ll only protect the data stored on your own PC, and that you’re still at risk from network admins and other snoopers if you’re using an insecure network to transmit and receive data. But as a step up from Firefox’s own Private Browsing mode, it’s well worth considering.
Private Browsing by PortableApps.com 3.0 is available, along with Firefox Portable 21.0, as free, open-source downloads for Windows PCs.