SSL crypting http-traffic

Hi I was presented a question: How would one build a system to crypt the http traffic going thru the LAN? I was thinking, would it be possible to build an external, public IP server somewhere, that then would be used as a kind of "proxy"? All surfing would go crypted (ssl?) to this "proxy", starting from LAN computer, going thru the firewall/router into internet, reaching finally the proxy, where the surfing would then be "uncrypted" to "normal" http traffic. Has anyone done this, or is there a better way to crypt the http-traffic in LAN? Jaska.