Squid is a software proxy server and web caching daemon which can be used as a web proxy for browsing the Internet and a reverse proxy to take load off web-servers.
Squid can be used as a personal web proxy cache to reduce bandwidth consumption. This is specially nice if you have little bandwidth. Squid leaks too much information. This configuration will allow you to use Squid together with Privoxy.
The chain will go Browser -> Squid -> Privoxy (-> Tor) -> Websites you visit
INTF=eth1 # internal network interface ONTF=eth0 # external default route / public interface
This configuration may leak DNS requests, so you may want a rule which prevents this:
..where 65533 is where dns-proxy-tor is listening.