A security researcher intercepted thousands of private e-mail messages sent by foreign embassies and human rights groups around the world by turning portions of the Tor internet anonymity service into his own private listening post.

This article explains how to set up Tor in Feisty based on my own experience (with Gnome interface). Tor is a program that allows one to surf through a local proxy with a routed IP address (so the webpage you surf does not have a record of your own IP address).