httptunnel. httptunnel creates a bidirectional virtual data path tunnelled in HTTP requests. The HTTP requests can be sent via an HTTP proxy if so desired. Or, on their system they install a Virtual Private Network (vpn). See:
Or, Maybe this user simply puts a modem on their NT system and turns on routing.
Finally, on the workstation, on the private LAN, change the default gateway to point to the new route to the Internet. Now, from this workstation, you can go anywhere. The only thing the firewall admin might see is one connect with nowill see is a really long DNS lookup.
Now, take over the world!