Anyway, today I installed Tor on Rohan the MacBook Pro. As described by its developers:
Tor is a software project that helps you defend against traffic analysis, a form of network surveillance that threatens personal freedom and privacy, confidential business activities and relationships, and state security. Tor protects you by bouncing your communications around a distributed network of relays run by volunteers all around the world: it prevents somebody watching your Internet connection from learning what sites you visit, and it prevents the sites you visit from learning your physical location. Tor works with many of your existing applications, including web browsers, instant messaging clients, remote login, and other applications based on the TCP protocol.
Hundreds of thousands of people around the world use Tor for a wide variety of reasons: journalists and bloggers, human rights workers, law enforcement officers, soldiers, corporations, citizens of repressive regimes, and just ordinary citizens. See the Who Uses Tor? page for examples of typical Tor users. See the overview page for a more detailed explanation of what Tor does, why this diversity of users is important, and how Tor works.
To make using Tor easier I downgraded Firefox from the latest version 3 release candidate back to v184.108.40.206, and installed the Torbutton extension, which hasn't yet been updated for FF3. Torbutton allows me to "Torify" my Firefox traffic with a single mouse click, and to disable it just as easily.
Compared with going directly to the Internet, web traffic through Tor is markedly slower. Since you're routing your traffic through a network of onion routers to obscure your trail, that stands to reason. So, I don't plan to use Tor by default.
However, there may be times when I need to research or relay sensitive information, on behalf of myself or others. Tor will help me do that in a more secure fashion. Another reason for me to try it is to see how Tor traffic looks on a LAN, so that I can recognize it (if that's possible).