Well, the system administrator can pull up a *wealth* of data on user usage of the system/network. He can also very easily block access to sites such as anonymizer.com and so forth.
What a friend of mine here does is he uses a little program he's written - it is executed Sunday night and basically looks for web usage during working hours for all users. he can adjust variables such as number of sites visited, bytes downloaded, total time spent etc. If it reaches above a specified level, it's reported in a log file and he manually checks out the user to see whether it's legitimate use or waste of company money.
According to him, more than a few have been caught in his net - most think it's impossible for an admin to keep an eye out on every user when there's so much traffic. It ain't

. And admins have a tendency to have a personality in line with the Bastard Operator From Hell

. In the company he works for, people get two warnings by mail. A third violation results in a face to face talk, and a fourth is grounds for firing.
If yer a nerd, you can beat the admin - there are several ways of spoofing 'im, or simply turning the data he receives into something that cannot be used as grounds for firing someone. If ya *ain't* a nerd, I would advice you *not* to try to outsmart the admin - these guys love such challenges (its their equivalent of hacking) and will probably spend their free time figuring things out, just for the fun of it.
Of course, many companies have an IT department that doesn't know what the hell they're doing. The Code Red and other viruses have proven that. The risk however is that you'll run across the dude that has run UNIX on his machines since his early teens and doesn't go to work - he goes to "play".
Hm, actually sounds fun to have that role. Am sorta undecided between admin and software development, but unfortunately I only started with UNIX two years ago, so I prolly lack the real expertise needed

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Ooops, getting long. What I wanted to say was: check the IT use contract - some (most?) companies or organisations have one ya have to sign on to. Then check the expertise of the IT department. THEN risk it, if everything is in your favour

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