I was reading an article on company employees wasting office hours playing online and taking care of personal business...
While I understand their concern about decreases in productivity, I also think businesses need to pick their battles and be careful not to generalize their policies about it, otherwise they risk alienating their employees in a big way.
There are some people who abuse the system, yes. But for those who make sure to get all their other important work done before taking care of personal things, punishing them as well as the abusers could really hurt the work place vibe.
As an employee, you have agreed to give up 40+ hours of your week to this company. Those hours are usually the only hours that everything else you may need to utilize (businesses, banks, doctors, etc...) are open as well. So you give up the opportunity to take care of some needs you may have so that you can be at your job during those hours. In exchange, I feel it is your right to take care of some of those things while you are at work. If all your work gets done still, what does it matter if you take an extra 10 min at lunch? Or spare 5 min to pay a bill or two online? Or call your credit card company to complain about a charge? These are things you simply cannot take care of properly sometimes due to the time spent at your job place.
I think it is unfortunate that we cannot treat people like the adults they are and trust them to get the work done first, then take care of personal things. But if we have to "restrict" their use of internet, I think simply expressing to the employees the expectations about internet use could be very beneficial to the employer. Let employees know that they can use computers for personal use, but only after work is done for the day, or as long as everything that needs attention right away gets attended to. Treating people like the freeminded adults they are is the first step in getting them to make smart decisions. Restricting their freedoms in a mass company policy is the first step in driving them away, or cutting morale, or undermining their intelligence.
If after giving them this talk about expectations, your employees still waste tons of time online, then it's time to take more action.

Says the girl who is online because there really is not much else for her to do sometimes...