Rosio Pavoris

In case you’re one of the three remaining peope who doesn’t know what Tor is, it’s basically an anonymising proxy on steroids.
Any request you make over a network (say, to retrieve a web page to display in your browser) is sent to a random node in the network, which then passes it on to the next node, which passes it on to the next node, and so on, until it finally reaches its destination. Each node only knows about the previous and the next node in the chain, so it becomes impossible to trace who made the original request.

Everything’s encrypted except for the final step between the last node and the webserver (for example), so some care should be taken when entering passwords and things, as a malicious exit node can intercept those if you don’t use things like TLS or other end-to-end encryption.
This is, of course, just as much of a risk on the internet in general (and one too many people aren’t aware of, too).

It’s pretty slow, since far more people are running clients than nodes (I’ll be setting up a node myself as soon as my ISP stops sucking; I’m giving it another week), but it’s not meant for general browsing (and certainly not filesharing) anyway; there’s a plug-in for Firefox that lets you turn it on briefly when you need it, and disable it when you don’t.

As with all privacy-preserving tools, genuinely undesirable activity is an issue (see picture), but the potential for good is considerable. While it may seem paranoid in (much of) the West (though maybe not even), much of China, for instance, depends on tools like these.
And you never know, you may need it yourself one day, and it’s better to become acquainted with it now than when it’s too late.

Get it here, if you don’t have it already. You don’t have to run a node (you can just set up the client (complete instructions for configuring Firefox to use it are there)), but if you can, please do. People depend on it.