I work for a rather prominent Australian business largely involved in the medical field. They have very strict guidelines about internet usage, and endless 'Standard Operating Procedures' that outline these rules. IE is the browser supplied to us on all PCs, and very aggressive filters monitor our activities.
However, about 2 years ago I did something rather clever. No executable can be run without sysadmin rights. Somehow they overlooked applying this rule to our 'My Documents' folder (a virtual doc folder that is accessible from any terminal). So, I created the folder 'FireFox' and ran the .exe there. And because FF uses a different range of ports, none of the filters was looking for traffic here

I have been able to browse TOG from work, check my gmail (a
monumental no-no) etc etc. All without being sniffed out.
...and this has been wonderful, until today. Someone in IS/IT finally found my traffic trail and blocked all ports FireFox uses.
Un.Freakin.Believable. Any FireFox user must feel my pain. Going back to IE (6!) behind aggressive firewalls -- as if the program isn't sluggy enough already!
I'm lucky if I can check Reuters from work now.
Bastards.