My workload changes on a minute to minute basis. If computer problems were fires, my job description would be fireman.
When it's slow, I'm all over the 'net.
When something comes up, fortunately, I pretty much drop my web browser for work at any time.
At my last job, I spent a lot of time surfing the 'net, and it wasn't out of laziness. It was poor management. Period. When you've got a team of versitile people under you, who have a desire to branch out into different endeavours and work hard, and you confine them, you're going to have a lot of internet traffic. The problem is - a poor manager thinks he or she needs to confine the workers to a specific set of tasks so that they can be more effectively measured. Rarely, do the things they measure, directly apply to "getting the job done right". Except maybe for sales people. It's pretty easy to measure sales people - "hey Bob, how much did you sell this week?"