Shell access via web browser?

[Paul Truran]

Hi All,

Have just started a new job, and due to foolishly restrictive network access, 
I am unable to connect to my BSD box during lunchtimes to have a play about 
with things.  No direct internet connection, only web access through a proxy 
server on port 80.  I'm sure there must be a way to get shell access through 
a web browser, but have been unable to to manage it as yet.  I have tried 
shellinabox, but haven't really had much luck with getting it working.  
Anyone have any ideas on how to get through?  Just shell acccess would do me, 
but if anyone can tell me how to get VNC working through the web proxy, that 
would be very useful as well!

Cheers,

Paul.