I set up a SSHD server on port 80 at home (solely because my work blocks everything except port 80 & 443 - default HTTP & HTTPS). I also have a Proxy Webserver setup at home using Apache on port 8888 (any port is fine), but it is restricted so that it only accepts connections from 127.0.0.1 (ie, the same PC that it resides on).
At work I setup my IE to use a proxy on 127.0.0.1 port 80 and run a SSH client to my home machine on port 80 (SSH is 22 by default, but you can override that) called PUTTY with port forwarding to port 8888.
So basically what my Network guys see is a SSH (securely encrypted) tunnel to my home LAN.
The flow is like this
A = my work PC
B = my home PC
on A, IE proxies HTTP requests to 127.0.0.1:80 (the Putty SSH client) who is connected securely to my home, B, on port 80 - but along with encryping the requests and responses it tells my machine B to have the SSHD server forward the HTTP request to my home proxy server 8888 ..
it does and sends the response back.
it's a beautiful thing
Of course, you have to worry about network guys using keystroke logger, remote desktop, or simply checking out your cached web pages