Squid3

Анонимный Proxy:

Находим в конфиге SQUID3

request_header_access

Добавляем:

#Anonim proxy =)
request_header_access X-Forwarded-For deny all
request_header_access Via deny all
request_header_access Cache-Control deny all

Перегружаем SQUID и проверяем:

http://whatismyipaddress.com/

http://ipaddressworld.com./

http://www.ipaddrs.com/