- Download and install Firefox 2
- Download and install the free Tor & Privoxy & Vidalia bundle
- Install the FoxTor Addon for firefox.
Done.
Now that will keep other computers from knowing your true identity, (if you are signing enemies up for spam, or hacking through your browser) but if you are trying to keep your computer from prying eyes you need to clear your cookies, cache, history, etc.. thankfully there is an easy solution for this as well. (Requires Firefox 2) Stealther
Once you have finally made the switch to firefox you will be able to install hundreds of "extensions" like these HERE