"Anonymous proxy servers hide your IP address and thereby prevent your from unauthorized access to your computer through the Internet. They do not provide anyone with your IP address and effectively hide any information about you and your reading interests. Besides that, they don?t even let anyone know that you are surfing through a proxy server. Anonymous proxy servers can be used for all kinds of Web-services, such as Web-Mail (MSN Hot Mail, Yahoo mail), web-chat rooms, FTP archives, etc."
*proxy4free.com/tips.html