Most companies monitor Internet use. When I was responsible for a very large staff, all of whom had internet access I had a clearly stated company policy that said stated the purpose of internet access in the workplace was work, and work related research. I told them that all users were monitored and that they probably did not want to be using the internet for anything that they didn't want to have public. That was about it. We had one case of misuse inthe two years I held that position, out of 130 or so people.

We had a similar policy about phones - we didn't monitor calls, of course, but did not have strict rules about who/when long distance calls were made - we simply let people know that we kept track of who called whom - and they might want to be sure they were comfortable explaining why they made the calls. I never saw abuse.